21117562536 has 48 divisors (see below), whose sum is σ = 61413323040. Its totient is φ = 6033588960.

The previous prime is 21117562523. The next prime is 21117562547. The reversal of 21117562536 is 63526571112.

It is a junction number, because it is equal to n+sod(n) for n = 21117562494 and 21117562503.

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, 8977380 + ... + 8979731.

It is an arithmetic number, because the mean of its divisors is an integer number (1279444230).

Almost surely, 2^21117562536 is an apocalyptic number.

It is an amenable number.

21117562536 is an abundant number, since it is smaller than the sum of its proper divisors (40295760504).

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

21117562536 is a wasteful number, since it uses less digits than its factorization.

21117562536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17957134 (or 17957123 counting only the distinct ones).

The product of its digits is 75600, while the sum is 39.

The spelling of 21117562536 in words is "twenty-one billion, one hundred seventeen million, five hundred sixty-two thousand, five hundred thirty-six".