21120212200 has 48 divisors (see below), whose sum is σ = 49287163500. Its totient is φ = 8416657920.

The previous prime is 21120212189. The next prime is 21120212237. The reversal of 21120212200 is 221202112.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 2983125924 + 18137086276 = 54618^2 + 134674^2 .

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, 142485 + ... + 250084.

Almost surely, 2^21120212200 is an apocalyptic number.

21120212200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21120212200 is an abundant number, since it is smaller than the sum of its proper divisors (28166951300).

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

21120212200 is a wasteful number, since it uses less digits than its factorization.

21120212200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 392854 (or 392845 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 21120212200 its reverse (221202112), we get a palindrome (21341414312).

The spelling of 21120212200 in words is "twenty-one billion, one hundred twenty million, two hundred twelve thousand, two hundred".