165978435584 has 104 divisors (see below), whose sum is σ = 376263741840. Its totient is φ = 72573124608.

The previous prime is 165978435563. The next prime is 165978435589. The reversal of 165978435584 is 485534879561.

It is a tau number, because it is divible by the number of its divisors (104).

It is a self number, because there is not a number n which added to its sum of digits gives 165978435584.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165978435589) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 929684 + ... + 1093740.

Almost surely, 2^165978435584 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 165978435584, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (188131870920).

165978435584 is an abundant number, since it is smaller than the sum of its proper divisors (210285306256).

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

165978435584 is a wasteful number, since it uses less digits than its factorization.

165978435584 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 164113 (or 164091 counting only the distinct ones).

The product of its digits is 145152000, while the sum is 65.

The spelling of 165978435584 in words is "one hundred sixty-five billion, nine hundred seventy-eight million, four hundred thirty-five thousand, five hundred eighty-four".