2256761521 has 4 divisors (see below), whose sum is σ = 2579156032. Its totient is φ = 1934367012.

The previous prime is 2256761491. The next prime is 2256761539. The reversal of 2256761521 is 1251676522.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2256761521 - 2⁹ = 2256761009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2256761581) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 161197245 + ... + 161197258.

It is an arithmetic number, because the mean of its divisors is an integer number (644789008).

Almost surely, 2^2256761521 is an apocalyptic number.

It is an amenable number.

2256761521 is a deficient number, since it is larger than the sum of its proper divisors (322394511).

2256761521 is an equidigital number, since it uses as much as digits as its factorization.

2256761521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 322394510.

The product of its digits is 50400, while the sum is 37.

The square root of 2256761521 is about 47505.3841264335. The cubic root of 2256761521 is about 1311.6819917048.

The spelling of 2256761521 in words is "two billion, two hundred fifty-six million, seven hundred sixty-one thousand, five hundred twenty-one".