21268998900 has 72 divisors (see below), whose sum is σ = 68375901440. Its totient is φ = 5671732320.

The previous prime is 21268998889. The next prime is 21268998929. The reversal of 21268998900 is 989986212.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

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, 3936004 + ... + 3941403.

Almost surely, 2^21268998900 is an apocalyptic number.

21268998900 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21268998900 is an abundant number, since it is smaller than the sum of its proper divisors (47106902540).

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

21268998900 is a wasteful number, since it uses less digits than its factorization.

21268998900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7877430 (or 7877417 counting only the distinct ones).

The product of its (nonzero) digits is 1119744, while the sum is 54.

The spelling of 21268998900 in words is "twenty-one billion, two hundred sixty-eight million, nine hundred ninety-eight thousand, nine hundred".