166681833667 has 4 divisors (see below), whose sum is σ = 167471795176. Its totient is φ = 165891872160.

The previous prime is 166681833613. The next prime is 166681833677. The reversal of 166681833667 is 766338186661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 766338186661 = 67 ⋅11437883383.

It is a cyclic number.

It is not a de Polignac number, because 166681833667 - 2³⁵ = 132322095299 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166681833607) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 394980438 + ... + 394980859.

It is an arithmetic number, because the mean of its divisors is an integer number (41867948794).

Almost surely, 2^166681833667 is an apocalyptic number.

166681833667 is a deficient number, since it is larger than the sum of its proper divisors (789961509).

166681833667 is an equidigital number, since it uses as much as digits as its factorization.

166681833667 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 789961508.

The product of its digits is 31352832, while the sum is 61.

The spelling of 166681833667 in words is "one hundred sixty-six billion, six hundred eighty-one million, eight hundred thirty-three thousand, six hundred sixty-seven".