256307765 has 16 divisors (see below), whose sum is σ = 353458560. Its totient is φ = 174778560.

The previous prime is 256307761. The next prime is 256307767. The reversal of 256307765 is 567703652.

It is not a de Polignac number, because 256307765 - 2² = 256307761 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256307761) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13895 + ... + 26564.

It is an arithmetic number, because the mean of its divisors is an integer number (22091160).

Almost surely, 2^256307765 is an apocalyptic number.

It is an amenable number.

256307765 is a deficient number, since it is larger than the sum of its proper divisors (97150795).

256307765 is a wasteful number, since it uses less digits than its factorization.

256307765 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40652.

The product of its (nonzero) digits is 264600, while the sum is 41.

The square root of 256307765 is about 16009.6147673828. The cubic root of 256307765 is about 635.2147701818.

The spelling of 256307765 in words is "two hundred fifty-six million, three hundred seven thousand, seven hundred sixty-five".