21244502100 has 72 divisors (see below), whose sum is σ = 61859075488. Its totient is φ = 5629104000.

The previous prime is 21244502077. The next prime is 21244502159. The reversal of 21244502100 is 120544212.

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, 178426 + ... + 272625.

Almost surely, 2^21244502100 is an apocalyptic number.

21244502100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21244502100 is an abundant number, since it is smaller than the sum of its proper divisors (40614573388).

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

21244502100 is a wasteful number, since it uses less digits than its factorization.

21244502100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 451225 (or 451218 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 21.

The spelling of 21244502100 in words is "twenty-one billion, two hundred forty-four million, five hundred two thousand, one hundred".