165709225 has 24 divisors (see below), whose sum is σ = 224753472. Its totient is φ = 120196800.

The previous prime is 165709177. The next prime is 165709259. The reversal of 165709225 is 522907561.

It is not a de Polignac number, because 165709225 - 2⁷ = 165709097 is a prime.

It is a hoax number, since the sum of its digits (37) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 168084 + ... + 169066.

It is an arithmetic number, because the mean of its divisors is an integer number (9364728).

Almost surely, 2^165709225 is an apocalyptic number.

It is an amenable number.

165709225 is a deficient number, since it is larger than the sum of its proper divisors (59044247).

165709225 is a wasteful number, since it uses less digits than its factorization.

165709225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1617 (or 1612 counting only the distinct ones).

The product of its (nonzero) digits is 37800, while the sum is 37.

The square root of 165709225 is about 12872.8095224003. The cubic root of 165709225 is about 549.2653828690.

The spelling of 165709225 in words is "one hundred sixty-five million, seven hundred nine thousand, two hundred twenty-five".