172211720256 has 63 divisors (see below), whose sum is σ = 493642351423. Its totient is φ = 57400586880.

The previous prime is 172211720227. The next prime is 172211720267. The reversal of 172211720256 is 652027112271.

The square root of 172211720256 is 414984.

It is a perfect power (a square), and thus also a powerful number.

172211720256 is a `hidden beast` number, since 17 + 221 + 172 + 0 + 256 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 172211720256.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 9950971 + ... + 9968261.

Almost surely, 2^172211720256 is an apocalyptic number.

172211720256 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

172211720256 is the 414984-th square number.

It is an amenable number.

172211720256 is an abundant number, since it is smaller than the sum of its proper divisors (321430631167).

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

172211720256 is an frugal number, since it uses more digits than its factorization.

172211720256 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34600 (or 17296 counting only the distinct ones).

The product of its (nonzero) digits is 23520, while the sum is 36.

Multiplying 172211720256 by its sum of digits (36), we get a square (6199621929216 = 2489904²).

172211720256 divided by its sum of digits (36) gives a square (4783658896 = 69164²).

The spelling of 172211720256 in words is "one hundred seventy-two billion, two hundred eleven million, seven hundred twenty thousand, two hundred fifty-six".