21937956 has 48 divisors (see below), whose sum is σ = 55964160. Its totient is φ = 6658560.

The previous prime is 21937943. The next prime is 21937969. The reversal of 21937956 is 65973912.

It is an interprime number because it is at equal distance from previous prime (21937943) and next prime (21937969).

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, 4590 + ... + 8058.

It is an arithmetic number, because the mean of its divisors is an integer number (1165920).

Almost surely, 2^21937956 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21937956, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27982080).

21937956 is an abundant number, since it is smaller than the sum of its proper divisors (34026204).

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

21937956 is a wasteful number, since it uses less digits than its factorization.

21937956 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3524 (or 3522 counting only the distinct ones).

The product of its digits is 102060, while the sum is 42.

The square root of 21937956 is about 4683.7971775046. The cubic root of 21937956 is about 279.9402763776.

The spelling of 21937956 in words is "twenty-one million, nine hundred thirty-seven thousand, nine hundred fifty-six".