21312208824 has 16 divisors (see below), whose sum is σ = 53280522120. Its totient is φ = 7104069600.

The previous prime is 21312208807. The next prime is 21312208843. The reversal of 21312208824 is 42880221312.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 444004327 + ... + 444004374.

Almost surely, 2^21312208824 is an apocalyptic number.

21312208824 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21312208824 is an abundant number, since it is smaller than the sum of its proper divisors (31968313296).

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

21312208824 is a wasteful number, since it uses less digits than its factorization.

21312208824 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 888008710 (or 888008706 counting only the distinct ones).

The product of its (nonzero) digits is 12288, while the sum is 33.

The spelling of 21312208824 in words is "twenty-one billion, three hundred twelve million, two hundred eight thousand, eight hundred twenty-four".