21202100021200 has 90 divisors (see below), whose sum is σ = 59254460915046. Its totient is φ = 7269291429120.

The previous prime is 21202100021117. The next prime is 21202100021239. The reversal of 21202100021200 is 212000120212.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 63659326864 + 21138440694336 = 252308^2 + 4597656^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 540850299 + ... + 540889498.

Almost surely, 2^{21202100021200} is an apocalyptic number.

21202100021200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21202100021200 is an abundant number, since it is smaller than the sum of its proper divisors (38052360893846).

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

21202100021200 is a wasteful number, since it uses less digits than its factorization.

21202100021200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1081739829 (or 1081739811 counting only the distinct ones).

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

Adding to 21202100021200 its reverse (212000120212), we get a palindrome (21414100141412).

The spelling of 21202100021200 in words is "twenty-one trillion, two hundred two billion, one hundred million, twenty-one thousand, two hundred".