256631215461040 has 80 divisors (see below), whose sum is σ = 682144150605120. Its totient is φ = 87957090524160.

The previous prime is 256631215461029. The next prime is 256631215461073. The reversal of 256631215461040 is 40164512136652.

It is a tau number, because it is divible by the number of its divisors (80).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 78486975 + ... + 81691294.

It is an arithmetic number, because the mean of its divisors is an integer number (8526801882564).

Almost surely, 2^{256631215461040} is an apocalyptic number.

256631215461040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

256631215461040 is an abundant number, since it is smaller than the sum of its proper divisors (425512935144080).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

256631215461040 is a wasteful number, since it uses less digits than its factorization.

256631215461040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 160181150 (or 160181144 counting only the distinct ones).

The product of its (nonzero) digits is 1036800, while the sum is 46.

Adding to 256631215461040 its reverse (40164512136652), we get a palindrome (296795727597692).

The spelling of 256631215461040 in words is "two hundred fifty-six trillion, six hundred thirty-one billion, two hundred fifteen million, four hundred sixty-one thousand, forty".