21460642666256 has 20 divisors (see below), whose sum is σ = 43387821043392. Its totient is φ = 10263785622816.

The previous prime is 21460642666249. The next prime is 21460642666289. The reversal of 21460642666256 is 65266624606412.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29158481516 + ... + 29158482251.

Almost surely, 2^{21460642666256} is an apocalyptic number.

It is an amenable number.

21460642666256 is an abundant number, since it is smaller than the sum of its proper divisors (21927178377136).

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

21460642666256 is a wasteful number, since it uses less digits than its factorization.

21460642666256 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58316963798 (or 58316963792 counting only the distinct ones).

The product of its (nonzero) digits is 29859840, while the sum is 56.

The spelling of 21460642666256 in words is "twenty-one trillion, four hundred sixty billion, six hundred forty-two million, six hundred sixty-six thousand, two hundred fifty-six".