21683317818840 has 64 divisors (see below), whose sum is σ = 65051882235360. Its totient is φ = 5782046638080.

The previous prime is 21683317818821. The next prime is 21683317818857. The reversal of 21683317818840 is 4881871338612.

It is a Harshad number since it is a multiple of its sum of digits (60).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1411032 + ... + 6734808.

Almost surely, 2^{21683317818840} is an apocalyptic number.

21683317818840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21683317818840 is an abundant number, since it is smaller than the sum of its proper divisors (43368564416520).

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

21683317818840 is a wasteful number, since it uses less digits than its factorization.

21683317818840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5357732 (or 5357728 counting only the distinct ones).

The product of its (nonzero) digits is 12386304, while the sum is 60.

The spelling of 21683317818840 in words is "twenty-one trillion, six hundred eighty-three billion, three hundred seventeen million, eight hundred eighteen thousand, eight hundred forty".