21872507400 has 144 divisors (see below), whose sum is σ = 77321353200. Its totient is φ = 5525677440.

The previous prime is 21872507357. The next prime is 21872507401. The reversal of 21872507400 is 470527812.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (21872507401) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 285574 + ... + 353973.

Almost surely, 2^21872507400 is an apocalyptic number.

21872507400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21872507400 is an abundant number, since it is smaller than the sum of its proper divisors (55448845800).

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

21872507400 is a wasteful number, since it uses less digits than its factorization.

21872507400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 639588 (or 639576 counting only the distinct ones).

The product of its (nonzero) digits is 31360, while the sum is 36.

The spelling of 21872507400 in words is "twenty-one billion, eight hundred seventy-two million, five hundred seven thousand, four hundred".