21681126955 has 16 divisors (see below), whose sum is σ = 27733363200. Its totient is φ = 16224006240.

The previous prime is 21681126941. The next prime is 21681126959. The reversal of 21681126955 is 55962118612.

It is not a de Polignac number, because 21681126955 - 2²⁷ = 21546909227 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21681126959) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1436941 + ... + 1451950.

It is an arithmetic number, because the mean of its divisors is an integer number (1733335200).

Almost surely, 2^21681126955 is an apocalyptic number.

21681126955 is a deficient number, since it is larger than the sum of its proper divisors (6052236245).

21681126955 is a wasteful number, since it uses less digits than its factorization.

21681126955 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2888994.

The product of its digits is 259200, while the sum is 46.

The spelling of 21681126955 in words is "twenty-one billion, six hundred eighty-one million, one hundred twenty-six thousand, nine hundred fifty-five".