21308952 has 32 divisors (see below), whose sum is σ = 60883200. Its totient is φ = 6088224.

The previous prime is 21308941. The next prime is 21308953. The reversal of 21308952 is 25980312.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21308953) 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, 63252 + ... + 63587.

It is an arithmetic number, because the mean of its divisors is an integer number (1902600).

Almost surely, 2^21308952 is an apocalyptic number.

It is an amenable number.

21308952 is an abundant number, since it is smaller than the sum of its proper divisors (39574248).

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

21308952 is a wasteful number, since it uses less digits than its factorization.

21308952 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126855 (or 126851 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 30.

The square root of 21308952 is about 4616.1620422165. The cubic root of 21308952 is about 277.2388127617.

The spelling of 21308952 in words is "twenty-one million, three hundred eight thousand, nine hundred fifty-two".