21996011856 has 80 divisors (see below), whose sum is σ = 69936051584. Its totient is φ = 5801144832.

The previous prime is 21996011819. The next prime is 21996011893. The reversal of 21996011856 is 65811069912.

It is an interprime number because it is at equal distance from previous prime (21996011819) and next prime (21996011893).

It is a Harshad number since it is a multiple of its sum of digits (48).

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, 2513491 + ... + 2522226.

Almost surely, 2^21996011856 is an apocalyptic number.

21996011856 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

21996011856 is an abundant number, since it is smaller than the sum of its proper divisors (47940039728).

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

21996011856 is a wasteful number, since it uses less digits than its factorization.

21996011856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5035748 (or 5035742 counting only the distinct ones).

The product of its (nonzero) digits is 233280, while the sum is 48.

The spelling of 21996011856 in words is "twenty-one billion, nine hundred ninety-six million, eleven thousand, eight hundred fifty-six".