166665166 has 4 divisors (see below), whose sum is σ = 249997752. Its totient is φ = 83332582.

The previous prime is 166665157. The next prime is 166665167. The reversal of 166665166 is 661566661.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166665167) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41666290 + ... + 41666293.

It is an arithmetic number, because the mean of its divisors is an integer number (62499438).

Almost surely, 2^166665166 is an apocalyptic number.

166665166 is a deficient number, since it is larger than the sum of its proper divisors (83332586).

166665166 is an equidigital number, since it uses as much as digits as its factorization.

166665166 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83332585.

The product of its digits is 233280, while the sum is 43.

The square root of 166665166 is about 12909.8863666571. The cubic root of 166665166 is about 550.3195564468.

The spelling of 166665166 in words is "one hundred sixty-six million, six hundred sixty-five thousand, one hundred sixty-six".