21722308 has 12 divisors (see below), whose sum is σ = 38549952. Its totient is φ = 10708040.

The previous prime is 21722297. The next prime is 21722317. The reversal of 21722308 is 80322712.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 37960 + ... + 38527.

It is an arithmetic number, because the mean of its divisors is an integer number (3212496).

Almost surely, 2^21722308 is an apocalyptic number.

It is an amenable number.

21722308 is a deficient number, since it is larger than the sum of its proper divisors (16827644).

21722308 is a wasteful number, since it uses less digits than its factorization.

21722308 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76562 (or 76560 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 25.

The square root of 21722308 is about 4660.7196869153. The cubic root of 21722308 is about 279.0199923153.

The spelling of 21722308 in words is "twenty-one million, seven hundred twenty-two thousand, three hundred eight".