21351630620 has 24 divisors (see below), whose sum is σ = 44882905200. Its totient is φ = 8532179712.

The previous prime is 21351630617. The next prime is 21351630659. The reversal of 21351630620 is 2603615312.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 508850 + ... + 549209.

It is an arithmetic number, because the mean of its divisors is an integer number (1870121050).

Almost surely, 2^21351630620 is an apocalyptic number.

21351630620 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21351630620 is an abundant number, since it is smaller than the sum of its proper divisors (23531274580).

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

21351630620 is a wasteful number, since it uses less digits than its factorization.

21351630620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1059077 (or 1059075 counting only the distinct ones).

The product of its (nonzero) digits is 6480, while the sum is 29.

The spelling of 21351630620 in words is "twenty-one billion, three hundred fifty-one million, six hundred thirty thousand, six hundred twenty".