21426661461615 has 32 divisors (see below), whose sum is σ = 34347688030656. Its totient is φ = 11405895674880.

The previous prime is 21426661461607. The next prime is 21426661461617. The reversal of 21426661461615 is 51616416662412.

It is not a de Polignac number, because 21426661461615 - 2³ = 21426661461607 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21426661461617) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 17042925 + ... + 18256905.

It is an arithmetic number, because the mean of its divisors is an integer number (1073365250958).

Almost surely, 2^{21426661461615} is an apocalyptic number.

21426661461615 is a deficient number, since it is larger than the sum of its proper divisors (12921026569041).

21426661461615 is a wasteful number, since it uses less digits than its factorization.

21426661461615 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1216219.

The product of its digits is 2488320, while the sum is 51.

The spelling of 21426661461615 in words is "twenty-one trillion, four hundred twenty-six billion, six hundred sixty-one million, four hundred sixty-one thousand, six hundred fifteen".