21956324 has 48 divisors (see below), whose sum is σ = 44311680. Its totient is φ = 9434880.

The previous prime is 21956323. The next prime is 21956351. The reversal of 21956324 is 42365912.

21956324 = T₂₀₇ + T₂₀₈ + ... + T₅₁₉.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21956321) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 69992 + ... + 70304.

It is an arithmetic number, because the mean of its divisors is an integer number (923160).

Almost surely, 2^21956324 is an apocalyptic number.

It is an amenable number.

21956324 is an abundant number, since it is smaller than the sum of its proper divisors (22355356).

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

21956324 is a wasteful number, since it uses less digits than its factorization.

21956324 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 420 (or 418 counting only the distinct ones).

The product of its digits is 12960, while the sum is 32.

The square root of 21956324 is about 4685.7575694865. The cubic root of 21956324 is about 280.0183831468.

The spelling of 21956324 in words is "twenty-one million, nine hundred fifty-six thousand, three hundred twenty-four".