172857155 has 16 divisors (see below), whose sum is σ = 224251680. Its totient is φ = 127464192.

The previous prime is 172857151. The next prime is 172857161. The reversal of 172857155 is 551758271.

172857155 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 172857155 - 2² = 172857151 is a prime.

It is not an unprimeable number, because it can be changed into a prime (172857151) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21074 + ... + 28103.

It is an arithmetic number, because the mean of its divisors is an integer number (14015730).

Almost surely, 2^172857155 is an apocalyptic number.

172857155 is a deficient number, since it is larger than the sum of its proper divisors (51394525).

172857155 is a wasteful number, since it uses less digits than its factorization.

172857155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49238.

The product of its digits is 98000, while the sum is 41.

The square root of 172857155 is about 13147.5151644712. The cubic root of 172857155 is about 557.0520629887.

The spelling of 172857155 in words is "one hundred seventy-two million, eight hundred fifty-seven thousand, one hundred fifty-five".