21972639722 has 16 divisors (see below), whose sum is σ = 36832186944. Its totient is φ = 9743964000.

The previous prime is 21972639721. The next prime is 21972639727. The reversal of 21972639722 is 22793627912.

It is not an unprimeable number, because it can be changed into a prime (21972639721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12179054 + ... + 12180857.

It is an arithmetic number, because the mean of its divisors is an integer number (2302011684).

Almost surely, 2^21972639722 is an apocalyptic number.

21972639722 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21972639722 is a deficient number, since it is larger than the sum of its proper divisors (14859547222).

21972639722 is a wasteful number, since it uses less digits than its factorization.

21972639722 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24359965.

The product of its digits is 1143072, while the sum is 50.

The spelling of 21972639722 in words is "twenty-one billion, nine hundred seventy-two million, six hundred thirty-nine thousand, seven hundred twenty-two".