21010021120100 has 72 divisors (see below), whose sum is σ = 49938220702440. Its totient is φ = 7636908267520.

The previous prime is 21010021120063. The next prime is 21010021120139. The reversal of 21010021120100 is 102112001012.

It can be written as a sum of positive squares in 12 ways, for example, as 5215230881344 + 15794790238756 = 2283688^2 + 3974266^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 213034079 + ... + 213132678.

It is an arithmetic number, because the mean of its divisors is an integer number (693586398645).

Almost surely, 2^{21010021120100} is an apocalyptic number.

21010021120100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21010021120100 is an abundant number, since it is smaller than the sum of its proper divisors (28928199582340).

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

21010021120100 is a wasteful number, since it uses less digits than its factorization.

21010021120100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 426166817 (or 426166810 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 21010021120100 its reverse (102112001012), we get a palindrome (21112133121112).

The spelling of 21010021120100 in words is "twenty-one trillion, ten billion, twenty-one million, one hundred twenty thousand, one hundred".