165917446593978 has 32 divisors (see below), whose sum is σ = 333089798279040. Its totient is φ = 55096691002560.

The previous prime is 165917446593967. The next prime is 165917446594093. The reversal of 165917446593978 is 879395644719561.

It is a self number, because there is not a number n which added to its sum of digits gives 165917446593978.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21994851 + ... + 28558857.

It is an arithmetic number, because the mean of its divisors is an integer number (10409056196220).

Almost surely, 2^{165917446593978} is an apocalyptic number.

165917446593978 is an abundant number, since it is smaller than the sum of its proper divisors (167172351685062).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

165917446593978 is a wasteful number, since it uses less digits than its factorization.

165917446593978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6579942.

The product of its digits is 12345177600, while the sum is 84.

The spelling of 165917446593978 in words is "one hundred sixty-five trillion, nine hundred seventeen billion, four hundred forty-six million, five hundred ninety-three thousand, nine hundred seventy-eight".