21722500172 has 24 divisors (see below), whose sum is σ = 39540221952. Its totient is φ = 10430643600.

The previous prime is 21722500169. The next prime is 21722500181. The reversal of 21722500172 is 27100522712.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 652388 + ... + 684875.

It is an arithmetic number, because the mean of its divisors is an integer number (1647509248).

Almost surely, 2^21722500172 is an apocalyptic number.

It is an amenable number.

21722500172 is a deficient number, since it is larger than the sum of its proper divisors (17817721780).

21722500172 is a wasteful number, since it uses less digits than its factorization.

21722500172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1337429 (or 1337427 counting only the distinct ones).

The product of its (nonzero) digits is 3920, while the sum is 29.

The spelling of 21722500172 in words is "twenty-one billion, seven hundred twenty-two million, five hundred thousand, one hundred seventy-two".