165663813979 has 2 divisors, whose sum is σ = 165663813980. Its totient is φ = 165663813978.

The previous prime is 165663813947. The next prime is 165663814003. The reversal of 165663813979 is 979318366561.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 165663813979 - 2⁵ = 165663813947 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 165663813979.

It is not a weakly prime, because it can be changed into another prime (165663816979) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82831906989 + 82831906990.

It is an arithmetic number, because the mean of its divisors is an integer number (82831906990).

Almost surely, 2^165663813979 is an apocalyptic number.

165663813979 is a deficient number, since it is larger than the sum of its proper divisors (1).

165663813979 is an equidigital number, since it uses as much as digits as its factorization.

165663813979 is an evil number, because the sum of its binary digits is even.

The product of its digits is 44089920, while the sum is 64.

The spelling of 165663813979 in words is "one hundred sixty-five billion, six hundred sixty-three million, eight hundred thirteen thousand, nine hundred seventy-nine".