165214664656621 has 8 divisors (see below), whose sum is σ = 168805928037600. Its totient is φ = 161656500477648.

The previous prime is 165214664656607. The next prime is 165214664656697. The reversal of 165214664656621 is 126656466412561.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 165214664656621 - 2¹⁷ = 165214664525549 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 165214664656621.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165214664656421) 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, 8274790411 + ... + 8274810376.

It is an arithmetic number, because the mean of its divisors is an integer number (21100741004700).

Almost surely, 2^{165214664656621} is an apocalyptic number.

It is an amenable number.

165214664656621 is a deficient number, since it is larger than the sum of its proper divisors (3591263380979).

165214664656621 is a wasteful number, since it uses less digits than its factorization.

165214664656621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16549601003.

The product of its digits is 74649600, while the sum is 61.

The spelling of 165214664656621 in words is "one hundred sixty-five trillion, two hundred fourteen billion, six hundred sixty-four million, six hundred fifty-six thousand, six hundred twenty-one".