2172799656 has 24 divisors (see below), whose sum is σ = 5884665930. Its totient is φ = 724266528.

The previous prime is 2172799649. The next prime is 2172799669. The reversal of 2172799656 is 6569972712.

It can be written as a sum of positive squares in only one way, i.e., 1431108900 + 741690756 = 37830^2 + 27234^2 .

It is a tau number, because it is divible by the number of its divisors (24).

It is a super-2 number, since 2×2172799656² = 9442116690227436672, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 15088815 + ... + 15088958.

Almost surely, 2^2172799656 is an apocalyptic number.

It is an amenable number.

2172799656 is an abundant number, since it is smaller than the sum of its proper divisors (3711866274).

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

2172799656 is a wasteful number, since it uses less digits than its factorization.

2172799656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30177785 (or 30177778 counting only the distinct ones).

The product of its digits is 2857680, while the sum is 54.

The square root of 2172799656 is about 46613.2991323292. The cubic root of 2172799656 is about 1295.2091225218.

The spelling of 2172799656 in words is "two billion, one hundred seventy-two million, seven hundred ninety-nine thousand, six hundred fifty-six".