21002212002120 has 64 divisors (see below), whose sum is σ = 63595483110720. Its totient is φ = 5548247902464.

The previous prime is 21002212002091. The next prime is 21002212002131. The reversal of 21002212002120 is 2120021220012.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 21002212002120.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 817830307 + ... + 817855986.

It is an arithmetic number, because the mean of its divisors is an integer number (993679423605).

Almost surely, 2^{21002212002120} is an apocalyptic number.

21002212002120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21002212002120 is an abundant number, since it is smaller than the sum of its proper divisors (42593271108600).

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

21002212002120 is a wasteful number, since it uses less digits than its factorization.

21002212002120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1635686414 (or 1635686410 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 21002212002120 its reverse (2120021220012), we get a palindrome (23122233222132).

The spelling of 21002212002120 in words is "twenty-one trillion, two billion, two hundred twelve million, two thousand, one hundred twenty".