21950575172 has 6 divisors (see below), whose sum is σ = 38413506558. Its totient is φ = 10975287584.

The previous prime is 21950575123. The next prime is 21950575181. The reversal of 21950575172 is 27157505912.

It can be written as a sum of positive squares in only one way, i.e., 20809216516 + 1141358656 = 144254^2 + 33784^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2743821893 + ... + 2743821900.

It is an arithmetic number, because the mean of its divisors is an integer number (6402251093).

Almost surely, 2^21950575172 is an apocalyptic number.

It is an amenable number.

21950575172 is a deficient number, since it is larger than the sum of its proper divisors (16462931386).

21950575172 is a wasteful number, since it uses less digits than its factorization.

21950575172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5487643797 (or 5487643795 counting only the distinct ones).

The product of its (nonzero) digits is 220500, while the sum is 44.

The spelling of 21950575172 in words is "twenty-one billion, nine hundred fifty million, five hundred seventy-five thousand, one hundred seventy-two".