21226372660 has 12 divisors (see below), whose sum is σ = 44575382628. Its totient is φ = 8490549056.

The previous prime is 21226372627. The next prime is 21226372667. The reversal of 21226372660 is 6627362212.

It can be written as a sum of positive squares in 2 ways, for example, as 10224040996 + 11002331664 = 101114^2 + 104892^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21226372667) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 530659297 + ... + 530659336.

It is an arithmetic number, because the mean of its divisors is an integer number (3714615219).

Almost surely, 2^21226372660 is an apocalyptic number.

21226372660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21226372660 is an abundant number, since it is smaller than the sum of its proper divisors (23349009968).

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

21226372660 is a wasteful number, since it uses less digits than its factorization.

21226372660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1061318642 (or 1061318640 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 37.

The spelling of 21226372660 in words is "twenty-one billion, two hundred twenty-six million, three hundred seventy-two thousand, six hundred sixty".