666165030621516 has 48 divisors (see below), whose sum is σ = 1773772754218080. Its totient is φ = 216053523443520.

The previous prime is 666165030621511. The next prime is 666165030621521. The reversal of 666165030621516 is 615126030561666.

It is an interprime number because it is at equal distance from previous prime (666165030621511) and next prime (666165030621521).

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

It is not an unprimeable number, because it can be changed into a prime (666165030621511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 83353978815 + ... + 83353986806.

It is an arithmetic number, because the mean of its divisors is an integer number (36953599046210).

Almost surely, 2^{666165030621516} is an apocalyptic number.

It is an amenable number.

666165030621516 is an abundant number, since it is smaller than the sum of its proper divisors (1107607723596564).

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

666165030621516 is a wasteful number, since it uses less digits than its factorization.

666165030621516 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 166707965671 (or 166707965663 counting only the distinct ones).

The product of its (nonzero) digits is 6998400, while the sum is 54.

The spelling of 666165030621516 in words is "six hundred sixty-six trillion, one hundred sixty-five billion, thirty million, six hundred twenty-one thousand, five hundred sixteen".