166861580 has 12 divisors (see below), whose sum is σ = 350409360. Its totient is φ = 66744624.

The previous prime is 166861567. The next prime is 166861589. The reversal of 166861580 is 85168661.

It is a happy number.

It is a hoax number, since the sum of its digits (41) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (166861589) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 4171520 + ... + 4171559.

It is an arithmetic number, because the mean of its divisors is an integer number (29200780).

Almost surely, 2^166861580 is an apocalyptic number.

166861580 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

166861580 is an abundant number, since it is smaller than the sum of its proper divisors (183547780).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

166861580 is a wasteful number, since it uses less digits than its factorization.

166861580 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8343088 (or 8343086 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 41.

The square root of 166861580 is about 12917.4912424975. The cubic root of 166861580 is about 550.5356544561.

The spelling of 166861580 in words is "one hundred sixty-six million, eight hundred sixty-one thousand, five hundred eighty".