166581825 has 24 divisors (see below), whose sum is σ = 278154816. Its totient is φ = 87960000.

The previous prime is 166581823. The next prime is 166581869. The reversal of 166581825 is 528185661.

It is not a de Polignac number, because 166581825 - 2¹ = 166581823 is a prime.

It is not an unprimeable number, because it can be changed into a prime (166581823) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3421 + ... + 18570.

It is an arithmetic number, because the mean of its divisors is an integer number (11589784).

Almost surely, 2^166581825 is an apocalyptic number.

166581825 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

166581825 is a deficient number, since it is larger than the sum of its proper divisors (111572991).

166581825 is a wasteful number, since it uses less digits than its factorization.

166581825 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22105 (or 22100 counting only the distinct ones).

The product of its digits is 115200, while the sum is 42.

The square root of 166581825 is about 12906.6581654586. The cubic root of 166581825 is about 550.2278119625.

The spelling of 166581825 in words is "one hundred sixty-six million, five hundred eighty-one thousand, eight hundred twenty-five".