diff --git a/fortuna.cpp b/fortuna.cpp
index fc509d4..260e051 100644
--- a/fortuna.cpp
+++ b/fortuna.cpp
@@ -45,7 +45,7 @@ Fortuna::~Fortuna() noexcept {
 }
 
 
-auto Fortuna::random_data(unsigned int n_bytes) -> void {
+auto Fortuna::random_data(const uint64_t n_bytes) -> void {
 	if (!this->continue_running.load()) {
 		return;
 	}
diff --git a/fortuna.h b/fortuna.h
index 07ad203..9e1d750 100644
--- a/fortuna.h
+++ b/fortuna.h
@@ -11,6 +11,7 @@
 #include <atomic>
 #include <cassert>
 #include <chrono>
+#include <cstdint>
 #include <exception>
 #include <latch>
 #include <memory>
@@ -22,6 +23,7 @@ namespace fortuna {
 class Fortuna final {
 public:
 	static constexpr const char NUM_OF_POOLS{32};
+	static constexpr const uint64_t two_pow_twenty{1048576};
 	std::mutex mtx;
 	std::mutex mtx_random_data;
 	std::mutex mtx_p_pools;
@@ -33,7 +35,7 @@ public:
 	Fortuna();
 	~Fortuna() noexcept;
 
-	[[optimize_for_synchronized]] auto random_data(unsigned int) -> void;
+	[[optimize_for_synchronized]] auto random_data(const uint64_t) -> void;
 
 	auto set_reseed_ctr_to_null() -> void {
 		std::scoped_lock sl(mtx_accu, print_mtx);
diff --git a/generator.cpp b/generator.cpp
index 6cab518..00f7054 100644
--- a/generator.cpp
+++ b/generator.cpp
@@ -150,7 +150,7 @@ auto Generator::generate_blocks(unsigned int k_blocks) -> std::string {
 	return r;
 }
 
-auto Generator::generate_random_data(const unsigned int& n) -> std::string {
+auto Generator::generate_random_data(const uint64_t& n) -> std::string {
 	std::lock_guard<std::recursive_mutex> lg(mtx);
 
 	if (n == 0) {
diff --git a/generator.h b/generator.h
index 81b3bd9..a1b90c6 100644
--- a/generator.h
+++ b/generator.h
@@ -28,7 +28,7 @@ public:
 	~Generator() noexcept;
 
 	/* n is the number of random bytes to generate */
-	auto generate_random_data(const unsigned int& n) -> std::string;
+	auto generate_random_data(const uint64_t& n) -> std::string;
 
 	auto reseed(const std::string& s) -> void;