172555656 has 96 divisors (see below), whose sum is σ = 540469440. Its totient is φ = 45505152.

The previous prime is 172555613. The next prime is 172555657. The reversal of 172555656 is 656555271.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is not an unprimeable number, because it can be changed into a prime (172555657) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9645 + ... + 20931.

It is an arithmetic number, because the mean of its divisors is an integer number (5629890).

Almost surely, 2^172555656 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 172555656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (270234720).

172555656 is an abundant number, since it is smaller than the sum of its proper divisors (367913784).

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

172555656 is a wasteful number, since it uses less digits than its factorization.

172555656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11323 (or 11312 counting only the distinct ones).

The product of its digits is 315000, while the sum is 42.

The square root of 172555656 is about 13136.0441533972. The cubic root of 172555656 is about 556.7280027713.

The spelling of 172555656 in words is "one hundred seventy-two million, five hundred fifty-five thousand, six hundred fifty-six".