165025521 has 12 divisors (see below), whose sum is σ = 239582772. Its totient is φ = 109457376.

The previous prime is 165025519. The next prime is 165025541. The reversal of 165025521 is 125520561.

165025521 is a `hidden beast` number, since 1 + 650 + 2 + 5 + 5 + 2 + 1 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 103245921 + 61779600 = 10161^2 + 7860^2 .

It is not a de Polignac number, because 165025521 - 2¹ = 165025519 is a prime.

It is not an unprimeable number, because it can be changed into a prime (165025541) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 44766 + ... + 48311.

It is an arithmetic number, because the mean of its divisors is an integer number (19965231).

Almost surely, 2^165025521 is an apocalyptic number.

It is an amenable number.

165025521 is a deficient number, since it is larger than the sum of its proper divisors (74557251).

165025521 is a wasteful number, since it uses less digits than its factorization.

165025521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93280 (or 93277 counting only the distinct ones).

The product of its (nonzero) digits is 3000, while the sum is 27.

The square root of 165025521 is about 12846.2259438327. The cubic root of 165025521 is about 548.5089321184.

The spelling of 165025521 in words is "one hundred sixty-five million, twenty-five thousand, five hundred twenty-one".