21200021210120 has 16 divisors (see below), whose sum is σ = 47700047722860. Its totient is φ = 8480008484032.

The previous prime is 21200021210113. The next prime is 21200021210161. The reversal of 21200021210120 is 2101212000212.

It can be written as a sum of positive squares in 2 ways, for example, as 20497405088836 + 702616121284 = 4527406^2 + 838222^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21200021210095 and 21200021210104.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 265000265087 + ... + 265000265166.

Almost surely, 2^{21200021210120} is an apocalyptic number.

21200021210120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21200021210120 is an abundant number, since it is smaller than the sum of its proper divisors (26500026512740).

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

21200021210120 is a wasteful number, since it uses less digits than its factorization.

21200021210120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 530000530264 (or 530000530260 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 21200021210120 its reverse (2101212000212), we get a palindrome (23301233210332).

The spelling of 21200021210120 in words is "twenty-one trillion, two hundred billion, twenty-one million, two hundred ten thousand, one hundred twenty".