21639858552 has 96 divisors (see below), whose sum is σ = 66829024080. Its totient is φ = 6266741760.

The previous prime is 21639858529. The next prime is 21639858557. The reversal of 21639858552 is 25585893612.

It is a happy number.

21639858552 is a `hidden beast` number, since 2 + 1 + 6 + 3 + 9 + 8 + 585 + 52 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21639858557) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 664074 + ... + 695897.

Almost surely, 2^21639858552 is an apocalyptic number.

It is an amenable number.

21639858552 is an abundant number, since it is smaller than the sum of its proper divisors (45189165528).

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

21639858552 is a wasteful number, since it uses less digits than its factorization.

21639858552 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1360013 (or 1360006 counting only the distinct ones).

The product of its digits is 5184000, while the sum is 54.

The spelling of 21639858552 in words is "twenty-one billion, six hundred thirty-nine million, eight hundred fifty-eight thousand, five hundred fifty-two".