166539025 has 27 divisors (see below), whose sum is σ = 216305011. Its totient is φ = 127191680.

The previous prime is 166539017. The next prime is 166539041. The reversal of 166539025 is 520935661.

The square root of 166539025 is 12905.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 13 ways, for example, as 148425489 + 18113536 = 12183^2 + 4256^2 .

It is not a de Polignac number, because 166539025 - 2³ = 166539017 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 1871181 + ... + 1871269.

Almost surely, 2^166539025 is an apocalyptic number.

166539025 is the 12905-th square number.

166539025 is the 6453-rd centered octagonal number.

It is an amenable number.

166539025 is a deficient number, since it is larger than the sum of its proper divisors (49765986).

166539025 is an frugal number, since it uses more digits than its factorization.

166539025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 246 (or 123 counting only the distinct ones).

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

The cubic root of 166539025 is about 550.1806844372.

The spelling of 166539025 in words is "one hundred sixty-six million, five hundred thirty-nine thousand, twenty-five".