165220625 has 10 divisors (see below), whose sum is σ = 206460474. Its totient is φ = 132176000.

The previous prime is 165220619. The next prime is 165220633. The reversal of 165220625 is 526022561.

It can be written as a sum of positive squares in 5 ways, for example, as 22202944 + 143017681 = 4712^2 + 11959^2 .

It is not a de Polignac number, because 165220625 - 2²⁰ = 164172049 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 131552 + ... + 132801.

Almost surely, 2^165220625 is an apocalyptic number.

It is an amenable number.

165220625 is a deficient number, since it is larger than the sum of its proper divisors (41239849).

165220625 is an frugal number, since it uses more digits than its factorization.

165220625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 264373 (or 264358 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 29.

The square root of 165220625 is about 12853.8175263227. The cubic root of 165220625 is about 548.7250080720.

The spelling of 165220625 in words is "one hundred sixty-five million, two hundred twenty thousand, six hundred twenty-five".