165221161065684 has 30 divisors (see below), whose sum is σ = 431920751305274. Its totient is φ = 55073720355120.

The previous prime is 165221161065659. The next prime is 165221161065691. The reversal of 165221161065684 is 486560161122561.

165221161065684 is a `hidden beast` number, since 1 + 6 + 5 + 2 + 2 + 11 + 61 + 0 + 6 + 568 + 4 = 666.

It can be written as a sum of positive squares in only one way, i.e., 150254151152400 + 14967009913284 = 12257820^2 + 3868722^2 .

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 165221161065684.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 254970927247 + ... + 254970927894.

Almost surely, 2^{165221161065684} is an apocalyptic number.

It is an amenable number.

165221161065684 is an abundant number, since it is smaller than the sum of its proper divisors (266699590239590).

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

165221161065684 is a wasteful number, since it uses less digits than its factorization.

165221161065684 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 509941855157 (or 509941855146 counting only the distinct ones).

The product of its (nonzero) digits is 4147200, while the sum is 54.

The spelling of 165221161065684 in words is "one hundred sixty-five trillion, two hundred twenty-one billion, one hundred sixty-one million, sixty-five thousand, six hundred eighty-four".