21012504000 has 112 divisors (see below), whose sum is σ = 69383367456. Its totient is φ = 5603328000.

The previous prime is 21012503951. The next prime is 21012504001. The reversal of 21012504000 is 40521012.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21012504001) 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, 413761 + ... + 461760.

Almost surely, 2^21012504000 is an apocalyptic number.

21012504000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21012504000 is an abundant number, since it is smaller than the sum of its proper divisors (48370863456).

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

21012504000 is an equidigital number, since it uses as much as digits as its factorization.

21012504000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 875551 (or 875531 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 15.

The spelling of 21012504000 in words is "twenty-one billion, twelve million, five hundred four thousand".