21113102100 has 72 divisors (see below), whose sum is σ = 64302377440. Its totient is φ = 5333834880.

The previous prime is 21113102093. The next prime is 21113102137. The reversal of 21113102100 is 120131112.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a congruent number.

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 23 ways as a sum of consecutive naturals, for example, 1846327 + ... + 1857726.

Almost surely, 2^21113102100 is an apocalyptic number.

21113102100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21113102100 is an abundant number, since it is smaller than the sum of its proper divisors (43189275340).

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

21113102100 is a wasteful number, since it uses less digits than its factorization.

21113102100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3704089 (or 3704082 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 12.

Adding to 21113102100 its reverse (120131112), we get a palindrome (21233233212).

The spelling of 21113102100 in words is "twenty-one billion, one hundred thirteen million, one hundred two thousand, one hundred".