21722672 has 20 divisors (see below), whose sum is σ = 43918320. Its totient is φ = 10388928.

The previous prime is 21722671. The next prime is 21722689. The reversal of 21722672 is 27622712.

It is not an unprimeable number, because it can be changed into a prime (21722671) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29147 + ... + 29882.

It is an arithmetic number, because the mean of its divisors is an integer number (2195916).

Almost surely, 2^21722672 is an apocalyptic number.

It is an amenable number.

21722672 is an abundant number, since it is smaller than the sum of its proper divisors (22195648).

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

21722672 is a wasteful number, since it uses less digits than its factorization.

21722672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59060 (or 59054 counting only the distinct ones).

The product of its digits is 4704, while the sum is 29.

The square root of 21722672 is about 4660.7587365149. The cubic root of 21722672 is about 279.0215508162.

The spelling of 21722672 in words is "twenty-one million, seven hundred twenty-two thousand, six hundred seventy-two".