165390625 has 32 divisors (see below), whose sum is σ = 216796320. Its totient is φ = 126000000.

The previous prime is 165390619. The next prime is 165390689. The reversal of 165390625 is 526093561.

165390625 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 16 ways, for example, as 73153809 + 92236816 = 8553^2 + 9604^2 .

It is not a de Polignac number, because 165390625 - 2⁵ = 165390593 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2265589 + ... + 2265661.

It is an arithmetic number, because the mean of its divisors is an integer number (6774885).

Almost surely, 2^165390625 is an apocalyptic number.

It is an amenable number.

165390625 is a deficient number, since it is larger than the sum of its proper divisors (51405695).

165390625 is an frugal number, since it uses more digits than its factorization.

165390625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137 (or 107 counting only the distinct ones).

The product of its (nonzero) digits is 48600, while the sum is 37.

The square root of 165390625 is about 12860.4286475996. The cubic root of 165390625 is about 548.9131429286.

The spelling of 165390625 in words is "one hundred sixty-five million, three hundred ninety thousand, six hundred twenty-five".