165663332460621 has 16 divisors (see below), whose sum is σ = 247599080968320. Its totient is φ = 109464856845120.

The previous prime is 165663332460581. The next prime is 165663332460673. The reversal of 165663332460621 is 126064233366561.

165663332460621 is a `hidden beast` number, since 1 + 6 + 5 + 6 + 6 + 3 + 3 + 3 + 2 + 4 + 6 + 0 + 621 = 666.

It is not a de Polignac number, because 165663332460621 - 2¹¹ = 165663332458573 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165663332460421) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27149018985 + ... + 27149025086.

It is an arithmetic number, because the mean of its divisors is an integer number (15474942560520).

Almost surely, 2^{165663332460621} is an apocalyptic number.

It is an amenable number.

165663332460621 is a deficient number, since it is larger than the sum of its proper divisors (81935748507699).

165663332460621 is a wasteful number, since it uses less digits than its factorization.

165663332460621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54298044193 (or 54298044187 counting only the distinct ones).

The product of its (nonzero) digits is 16796160, while the sum is 54.

The spelling of 165663332460621 in words is "one hundred sixty-five trillion, six hundred sixty-three billion, three hundred thirty-two million, four hundred sixty thousand, six hundred twenty-one".