21100112200 has 48 divisors (see below), whose sum is σ = 49078192500. Its totient is φ = 8436529920.

The previous prime is 21100112171. The next prime is 21100112227. The reversal of 21100112200 is 221100112.

It can be written as a sum of positive squares in 6 ways, for example, as 14953865796 + 6146246404 = 122286^2 + 78398^2 .

It is a Harshad number since it is a multiple of its sum of digits (10).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 489106 + ... + 530494.

Almost surely, 2^21100112200 is an apocalyptic number.

21100112200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21100112200 is an abundant number, since it is smaller than the sum of its proper divisors (27978080300).

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

21100112200 is a wasteful number, since it uses less digits than its factorization.

21100112200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43954 (or 43945 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 21100112200 its reverse (221100112), we get a palindrome (21321212312).

The spelling of 21100112200 in words is "twenty-one billion, one hundred million, one hundred twelve thousand, two hundred".