21898823544 has 48 divisors (see below), whose sum is σ = 63871571400. Its totient is φ = 6738099264.

The previous prime is 21898823519. The next prime is 21898823567. The reversal of 21898823544 is 44532889812.

21898823544 is a `hidden beast` number, since 2 + 1 + 8 + 98 + 8 + 2 + 3 + 544 = 666.

It is a super-2 number, since 2×21898823544² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

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, 11697154 + ... + 11699025.

Almost surely, 2^21898823544 is an apocalyptic number.

21898823544 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21898823544 is an abundant number, since it is smaller than the sum of its proper divisors (41972747856).

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

21898823544 is a wasteful number, since it uses less digits than its factorization.

21898823544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23396204 (or 23396197 counting only the distinct ones).

The product of its digits is 4423680, while the sum is 54.

The spelling of 21898823544 in words is "twenty-one billion, eight hundred ninety-eight million, eight hundred twenty-three thousand, five hundred forty-four".