21431237100 has 432 divisors, whose sum is σ = 78391482624. Its totient is φ = 4402022400.

The previous prime is 21431237071. The next prime is 21431237123. The reversal of 21431237100 is 173213412.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 45891067 + ... + 45891533.

Almost surely, 2^21431237100 is an apocalyptic number.

21431237100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21431237100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39195741312).

21431237100 is an abundant number, since it is smaller than the sum of its proper divisors (56960245524).

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

21431237100 is a wasteful number, since it uses less digits than its factorization.

21431237100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 586 (or 538 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 24.

The spelling of 21431237100 in words is "twenty-one billion, four hundred thirty-one million, two hundred thirty-seven thousand, one hundred".