21682992 has 40 divisors (see below), whose sum is σ = 56604016. Its totient is φ = 7151616.

The previous prime is 21682987. The next prime is 21683017. The reversal of 21682992 is 29928612.

It is a self number, because there is not a number n which added to its sum of digits gives 21682992.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2328 + ... + 6984.

Almost surely, 2^21682992 is an apocalyptic number.

It is a pronic number, being equal to 4656×4657.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21682992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28302008).

21682992 is an abundant number, since it is smaller than the sum of its proper divisors (34921024).

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

21682992 is a wasteful number, since it uses less digits than its factorization.

21682992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4765 (or 4759 counting only the distinct ones).

The product of its digits is 31104, while the sum is 39.

The square root of 21682992 is about 4656.4999731558. The cubic root of 21682992 is about 278.8515544896.

The spelling of 21682992 in words is "twenty-one million, six hundred eighty-two thousand, nine hundred ninety-two".