166816825 has 18 divisors (see below), whose sum is σ = 240626526. Its totient is φ = 114387840.

The previous prime is 166816813. The next prime is 166816877. The reversal of 166816825 is 528618661.

It can be written as a sum of positive squares in 3 ways, for example, as 58323769 + 108493056 = 7637^2 + 10416^2 .

It is not a de Polignac number, because 166816825 - 2⁷ = 166816697 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 66864 + ... + 69313.

Almost surely, 2^166816825 is an apocalyptic number.

It is an amenable number.

166816825 is a deficient number, since it is larger than the sum of its proper divisors (73809701).

166816825 is a wasteful number, since it uses less digits than its factorization.

166816825 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 136201 (or 136189 counting only the distinct ones).

The product of its digits is 138240, while the sum is 43.

The square root of 166816825 is about 12915.7587852979. The cubic root of 166816825 is about 550.4864291712.

The spelling of 166816825 in words is "one hundred sixty-six million, eight hundred sixteen thousand, eight hundred twenty-five".