166123666 has 4 divisors (see below), whose sum is σ = 249185502. Its totient is φ = 83061832.

The previous prime is 166123561. The next prime is 166123667. The reversal of 166123666 is 666321661.

166123666 is digitally balanced in base 2, 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 can be written as a sum of positive squares in only one way, i.e., 165868641 + 255025 = 12879^2 + 505^2 .

It is not an unprimeable number, because it can be changed into a prime (166123667) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41530915 + ... + 41530918.

Almost surely, 2^166123666 is an apocalyptic number.

166123666 is a deficient number, since it is larger than the sum of its proper divisors (83061836).

166123666 is an equidigital number, since it uses as much as digits as its factorization.

166123666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83061835.

The product of its digits is 46656, while the sum is 37.

The square root of 166123666 is about 12888.8970047867. The cubic root of 166123666 is about 549.7229083577.

The spelling of 166123666 in words is "one hundred sixty-six million, one hundred twenty-three thousand, six hundred sixty-six".