21905996 has 24 divisors (see below), whose sum is σ = 46390176. Its totient is φ = 8835840.

The previous prime is 21905977. The next prime is 21905999. The reversal of 21905996 is 69950912.

It is not an unprimeable number, because it can be changed into a prime (21905999) 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, 22535 + ... + 23486.

It is an arithmetic number, because the mean of its divisors is an integer number (1932924).

Almost surely, 2^21905996 is an apocalyptic number.

It is an amenable number.

21905996 is an abundant number, since it is smaller than the sum of its proper divisors (24484180).

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

21905996 is a wasteful number, since it uses less digits than its factorization.

21905996 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46049 (or 46047 counting only the distinct ones).

The product of its (nonzero) digits is 43740, while the sum is 41.

The square root of 21905996 is about 4680.3841722662. The cubic root of 21905996 is about 279.8042679687.

The spelling of 21905996 in words is "twenty-one million, nine hundred five thousand, nine hundred ninety-six".