256440765 has 96 divisors (see below), whose sum is σ = 505284480. Its totient is φ = 110562816.

The previous prime is 256440763. The next prime is 256440781. The reversal of 256440765 is 567044652.

It is not a de Polignac number, because 256440765 - 2¹ = 256440763 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256440763) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1129582 + ... + 1129808.

It is an arithmetic number, because the mean of its divisors is an integer number (5263380).

Almost surely, 2^256440765 is an apocalyptic number.

It is an amenable number.

256440765 is a deficient number, since it is larger than the sum of its proper divisors (248843715).

256440765 is a wasteful number, since it uses less digits than its factorization.

256440765 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 331 (or 324 counting only the distinct ones).

The product of its (nonzero) digits is 201600, while the sum is 39.

The square root of 256440765 is about 16013.7679825830. The cubic root of 256440765 is about 635.3246237343.

The spelling of 256440765 in words is "two hundred fifty-six million, four hundred forty thousand, seven hundred sixty-five".