256516537 has 4 divisors (see below), whose sum is σ = 264791296. Its totient is φ = 248241780.

The previous prime is 256516501. The next prime is 256516573. The reversal of 256516537 is 735615652.

256516537 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 an interprime number because it is at equal distance from previous prime (256516501) and next prime (256516573).

It is a cyclic number.

It is not a de Polignac number, because 256516537 - 2²⁷ = 122298809 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 256516537.

It is not an unprimeable number, because it can be changed into a prime (256516037) 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, 4137333 + ... + 4137394.

It is an arithmetic number, because the mean of its divisors is an integer number (66197824).

Almost surely, 2^256516537 is an apocalyptic number.

It is an amenable number.

256516537 is a deficient number, since it is larger than the sum of its proper divisors (8274759).

256516537 is an equidigital number, since it uses as much as digits as its factorization.

256516537 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8274758.

The product of its digits is 189000, while the sum is 40.

The square root of 256516537 is about 16016.1336470448. The cubic root of 256516537 is about 635.3871918896.

The spelling of 256516537 in words is "two hundred fifty-six million, five hundred sixteen thousand, five hundred thirty-seven".