1256904021415 has 16 divisors (see below), whose sum is σ = 1724283164160. Its totient is φ = 861612504480.

The previous prime is 1256904021379. The next prime is 1256904021437. The reversal of 1256904021415 is 5141204096521.

It is not a de Polignac number, because 1256904021415 - 2⁷ = 1256904021287 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5395531 + ... + 5623660.

It is an arithmetic number, because the mean of its divisors is an integer number (107767697760).

Almost surely, 2^{1256904021415} is an apocalyptic number.

1256904021415 is a deficient number, since it is larger than the sum of its proper divisors (467379142745).

1256904021415 is a wasteful number, since it uses less digits than its factorization.

1256904021415 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11022462.

The product of its (nonzero) digits is 86400, while the sum is 40.

The spelling of 1256904021415 in words is "one trillion, two hundred fifty-six billion, nine hundred four million, twenty-one thousand, four hundred fifteen".