21982156 has 24 divisors (see below), whose sum is σ = 46551456. Its totient is φ = 8866560.

The previous prime is 21982151. The next prime is 21982171. The reversal of 21982156 is 65128912.

It is a Harshad number since it is a multiple of its sum of digits (34).

It is not an unprimeable number, because it can be changed into a prime (21982151) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22615 + ... + 23566.

It is an arithmetic number, because the mean of its divisors is an integer number (1939644).

Almost surely, 2^21982156 is an apocalyptic number.

It is an amenable number.

21982156 is an abundant number, since it is smaller than the sum of its proper divisors (24569300).

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

21982156 is a wasteful number, since it uses less digits than its factorization.

21982156 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46209 (or 46207 counting only the distinct ones).

The product of its digits is 8640, while the sum is 34.

The square root of 21982156 is about 4688.5131971660. The cubic root of 21982156 is about 280.1281556201.

The spelling of 21982156 in words is "twenty-one million, nine hundred eighty-two thousand, one hundred fifty-six".