21867911783956 has 12 divisors (see below), whose sum is σ = 43735823567968. Its totient is φ = 9371962193112.

The previous prime is 21867911783897. The next prime is 21867911784041. The reversal of 21867911783956 is 65938711976812.

21867911783956 is an admirable number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 390498424686 + ... + 390498424741.

Almost surely, 2^{21867911783956} is an apocalyptic number.

It is an amenable number.

21867911783956 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21867911783956 is a wasteful number, since it uses less digits than its factorization.

21867911783956 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 780996849438 (or 780996849436 counting only the distinct ones).

The product of its digits is 274337280, while the sum is 73.

The spelling of 21867911783956 in words is "twenty-one trillion, eight hundred sixty-seven billion, nine hundred eleven million, seven hundred eighty-three thousand, nine hundred fifty-six".