21208932 has 24 divisors (see below), whose sum is σ = 54986400. Its totient is φ = 7069608.

The previous prime is 21208927. The next prime is 21208939. The reversal of 21208932 is 23980212.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 21208896 and 21208905.

It is not an unprimeable number, because it can be changed into a prime (21208939) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 98082 + ... + 98297.

It is an arithmetic number, because the mean of its divisors is an integer number (2291100).

Almost surely, 2^21208932 is an apocalyptic number.

It is an amenable number.

21208932 is an abundant number, since it is smaller than the sum of its proper divisors (33777468).

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

21208932 is a wasteful number, since it uses less digits than its factorization.

21208932 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 196392 (or 196384 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 21208932 is about 4605.3156243628. The cubic root of 21208932 is about 276.8043642879.

The spelling of 21208932 in words is "twenty-one million, two hundred eight thousand, nine hundred thirty-two".