256490646069 has 48 divisors (see below), whose sum is σ = 400876356096. Its totient is φ = 145444975200.

The previous prime is 256490646043. The next prime is 256490646101. The reversal of 256490646069 is 960646094652.

It is a happy number.

It is not a de Polignac number, because 256490646069 - 2²⁰ = 256489597493 is a prime.

It is a super-2 number, since 2×256490646069² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256490646869) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 10750984 + ... + 10774814.

It is an arithmetic number, because the mean of its divisors is an integer number (8351590752).

Almost surely, 2^256490646069 is an apocalyptic number.

It is an amenable number.

256490646069 is a deficient number, since it is larger than the sum of its proper divisors (144385710027).

256490646069 is a wasteful number, since it uses less digits than its factorization.

256490646069 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24406 (or 24399 counting only the distinct ones).

The product of its (nonzero) digits is 16796160, while the sum is 57.

The spelling of 256490646069 in words is "two hundred fifty-six billion, four hundred ninety million, six hundred forty-six thousand, sixty-nine".