166386566 has 4 divisors (see below), whose sum is σ = 249579852. Its totient is φ = 83193282.

The previous prime is 166386551. The next prime is 166386587. The reversal of 166386566 is 665683661.

166386566 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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

It is a self number, because there is not a number n which added to its sum of digits gives 166386566.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41596640 + ... + 41596643.

It is an arithmetic number, because the mean of its divisors is an integer number (62394963).

Almost surely, 2^166386566 is an apocalyptic number.

166386566 is a deficient number, since it is larger than the sum of its proper divisors (83193286).

166386566 is an equidigital number, since it uses as much as digits as its factorization.

166386566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83193285.

The product of its digits is 933120, while the sum is 47.

The square root of 166386566 is about 12899.0916734474. The cubic root of 166386566 is about 550.0127446083.

The spelling of 166386566 in words is "one hundred sixty-six million, three hundred eighty-six thousand, five hundred sixty-six".