256521600615 has 64 divisors (see below), whose sum is σ = 485397826560. Its totient is φ = 113187164160.

The previous prime is 256521600611. The next prime is 256521600667. The reversal of 256521600615 is 516006125652.

It is a happy number.

It is not a de Polignac number, because 256521600615 - 2² = 256521600611 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256521600611) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 11002120 + ... + 11025410.

It is an arithmetic number, because the mean of its divisors is an integer number (7584341040).

Almost surely, 2^256521600615 is an apocalyptic number.

256521600615 is a deficient number, since it is larger than the sum of its proper divisors (228876225945).

256521600615 is a wasteful number, since it uses less digits than its factorization.

256521600615 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26952.

The product of its (nonzero) digits is 108000, while the sum is 39.

The spelling of 256521600615 in words is "two hundred fifty-six billion, five hundred twenty-one million, six hundred thousand, six hundred fifteen".