21131439996 has 48 divisors (see below), whose sum is σ = 49695101568. Its totient is φ = 6988497600.

The previous prime is 21131439929. The next prime is 21131440019. The reversal of 21131439996 is 69993413112.

It is a happy number.

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, 1008951 + ... + 1029681.

It is an arithmetic number, because the mean of its divisors is an integer number (1035314616).

Almost surely, 2^21131439996 is an apocalyptic number.

It is an amenable number.

21131439996 is an abundant number, since it is smaller than the sum of its proper divisors (28563661572).

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

21131439996 is a wasteful number, since it uses less digits than its factorization.

21131439996 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21402 (or 21400 counting only the distinct ones).

The product of its digits is 314928, while the sum is 48.

The spelling of 21131439996 in words is "twenty-one billion, one hundred thirty-one million, four hundred thirty-nine thousand, nine hundred ninety-six".