166015625 has 22 divisors (see below), whose sum is σ = 219726558. Its totient is φ = 125000000.

The previous prime is 166015613. The next prime is 166015639. The reversal of 166015625 is 526510661.

It can be written as a sum of positive squares in 11 ways, for example, as 4700224 + 161315401 = 2168^2 + 12701^2 .

It is not a de Polignac number, because 166015625 - 2¹⁰ = 166014601 is a prime.

It is a super-2 number, since 2×166015625² = 55122375488281250, which contains 22 as substring.

It is a Duffinian number.

It is a nialpdrome in base 5.

It is a junction number, because it is equal to n+sod(n) for n = 166015591 and 166015600.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 21 ways as a sum of consecutive naturals, for example, 9765617 + ... + 9765633.

Almost surely, 2^166015625 is an apocalyptic number.

It is an amenable number.

166015625 is a deficient number, since it is larger than the sum of its proper divisors (53710933).

166015625 is an frugal number, since it uses more digits than its factorization.

166015625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67 (or 22 counting only the distinct ones).

The product of its (nonzero) digits is 10800, while the sum is 32.

The square root of 166015625 is about 12884.7050800552. The cubic root of 166015625 is about 549.6037090198.

The spelling of 166015625 in words is "one hundred sixty-six million, fifteen thousand, six hundred twenty-five".