21102002100100 has 36 divisors (see below), whose sum is σ = 45891544535284. Its totient is φ = 8422330798080.

The previous prime is 21102002100097. The next prime is 21102002100143. The reversal of 21102002100100 is 100120020112.

It can be written as a sum of positive squares in 6 ways, for example, as 28191753216 + 21073810346884 = 167904^2 + 4590622^2 .

It is a Harshad number since it is a multiple of its sum of digits (10).

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, 230829597 + ... + 230920996.

Almost surely, 2^{21102002100100} is an apocalyptic number.

21102002100100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21102002100100 is an abundant number, since it is smaller than the sum of its proper divisors (24789542435184).

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

21102002100100 is a wasteful number, since it uses less digits than its factorization.

21102002100100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 461751064 (or 461751057 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 21102002100100 its reverse (100120020112), we get a palindrome (21202122120212).

The spelling of 21102002100100 in words is "twenty-one trillion, one hundred two billion, two million, one hundred thousand, one hundred".