166999979758786 has 4 divisors (see below), whose sum is σ = 250499969638182. Its totient is φ = 83499989879392.

The previous prime is 166999979758757. The next prime is 166999979758837. The reversal of 166999979758786 is 687857979999661.

166999979758786 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., 109574941518025 + 57425038240761 = 10467805^2 + 7577931^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41749994939695 + ... + 41749994939698.

Almost surely, 2^{166999979758786} is an apocalyptic number.

166999979758786 is a deficient number, since it is larger than the sum of its proper divisors (83499989879396).

166999979758786 is an equidigital number, since it uses as much as digits as its factorization.

166999979758786 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83499989879395.

The product of its digits is 1399943139840, while the sum is 106.

The spelling of 166999979758786 in words is "one hundred sixty-six trillion, nine hundred ninety-nine billion, nine hundred seventy-nine million, seven hundred fifty-eight thousand, seven hundred eighty-six".