172747217 has 4 divisors (see below), whose sum is σ = 182908836. Its totient is φ = 162585600.

The previous prime is 172747213. The next prime is 172747219. The reversal of 172747217 is 712747271.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 712747271 = 8893 ⋅80147.

It can be written as a sum of positive squares in 2 ways, for example, as 129595456 + 43151761 = 11384^2 + 6569^2 .

It is a cyclic number.

It is not a de Polignac number, because 172747217 - 2² = 172747213 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (172747213) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5080784 + ... + 5080817.

It is an arithmetic number, because the mean of its divisors is an integer number (45727209).

Almost surely, 2^172747217 is an apocalyptic number.

172747217 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

It is an amenable number.

172747217 is a deficient number, since it is larger than the sum of its proper divisors (10161619).

172747217 is a wasteful number, since it uses less digits than its factorization.

172747217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10161618.

The product of its digits is 38416, while the sum is 38.

The square root of 172747217 is about 13143.3335573590. Note that the first 3 decimals coincide. The cubic root of 172747217 is about 556.9339419935.

The spelling of 172747217 in words is "one hundred seventy-two million, seven hundred forty-seven thousand, two hundred seventeen".