172945 has 4 divisors (see below), whose sum is σ = 207540. Its totient is φ = 138352.

The previous prime is 172933. The next prime is 172969. The reversal of 172945 is 549271.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 549271 = 19 ⋅28909.

It can be written as a sum of positive squares in 2 ways, for example, as 18496 + 154449 = 136^2 + 393^2 .

It is a cyclic number.

It is not a de Polignac number, because 172945 - 2⁹ = 172433 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17290 + ... + 17299.

It is an arithmetic number, because the mean of its divisors is an integer number (51885).

2¹⁷²⁹⁴⁵ is an apocalyptic number.

It is an amenable number.

172945 is a deficient number, since it is larger than the sum of its proper divisors (34595).

172945 is an equidigital number, since it uses as much as digits as its factorization.

172945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34594.

The product of its digits is 2520, while the sum is 28.

The square root of 172945 is about 415.8665651384. The cubic root of 172945 is about 55.7146410547.

The spelling of 172945 in words is "one hundred seventy-two thousand, nine hundred forty-five".