163666979 has 4 divisors (see below), whose sum is σ = 187047984. Its totient is φ = 140285976.

The previous prime is 163666963. The next prime is 163667017. The reversal of 163666979 is 979666361.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 163666979 - 2⁴ = 163666963 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 163666979.

It is not an unprimeable number, because it can be changed into a prime (163666379) 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, 11690492 + ... + 11690505.

It is an arithmetic number, because the mean of its divisors is an integer number (46761996).

Almost surely, 2^163666979 is an apocalyptic number.

163666979 is a deficient number, since it is larger than the sum of its proper divisors (23381005).

163666979 is an equidigital number, since it uses as much as digits as its factorization.

163666979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23381004.

The product of its digits is 2204496, while the sum is 53.

The square root of 163666979 is about 12793.2395819042. The cubic root of 163666979 is about 546.9996167671. Note that the first 3 decimals are identical.

The spelling of 163666979 in words is "one hundred sixty-three million, six hundred sixty-six thousand, nine hundred seventy-nine".