172272187 has 4 divisors (see below), whose sum is σ = 172305000. Its totient is φ = 172239376.

The previous prime is 172272179. The next prime is 172272193. The reversal of 172272187 is 781272271.

It is a semiprime because it is the product of two primes.

It is a 4-Lehmer number, since φ(172272187) divides (172272187-1)⁴.

It is a cyclic number.

It is not a de Polignac number, because 172272187 - 2³ = 172272179 is a prime.

It is a deceptive number, since it divides R_172272186.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (172272127) 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 3 ways as a sum of consecutive naturals, for example, 6562 + ... + 19687.

It is an arithmetic number, because the mean of its divisors is an integer number (43076250).

It is a Poulet number, since it divides 2^172272186-1.

Almost surely, 2^172272187 is an apocalyptic number.

172272187 is the 6563-rd decagonal number.

172272187 is a deficient number, since it is larger than the sum of its proper divisors (32813).

172272187 is an equidigital number, since it uses as much as digits as its factorization.

172272187 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32812.

The product of its digits is 21952, while the sum is 37.

The square root of 172272187 is about 13125.2499785718. The cubic root of 172272187 is about 556.4229772687.

The spelling of 172272187 in words is "one hundred seventy-two million, two hundred seventy-two thousand, one hundred eighty-seven".