21120112100 has 18 divisors (see below), whose sum is σ = 45830643474. Its totient is φ = 8448044800.

The previous prime is 21120112081. The next prime is 21120112133. The reversal of 21120112100 is 121102112.

It can be written as a sum of positive squares in 3 ways, for example, as 3272755264 + 17847356836 = 57208^2 + 133594^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 105600461 + ... + 105600660.

Almost surely, 2^21120112100 is an apocalyptic number.

21120112100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21120112100 is an abundant number, since it is smaller than the sum of its proper divisors (24710531374).

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

21120112100 is a wasteful number, since it uses less digits than its factorization.

21120112100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 211201135 (or 211201128 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 21120112100 its reverse (121102112), we get a palindrome (21241214212).

The spelling of 21120112100 in words is "twenty-one billion, one hundred twenty million, one hundred twelve thousand, one hundred".