665168100621 has 8 divisors (see below), whose sum is σ = 910860822624. Its totient is φ = 431460389520.

The previous prime is 665168100599. The next prime is 665168100637. The reversal of 665168100621 is 126001861566.

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

It is not a de Polignac number, because 665168100621 - 2⁵ = 665168100589 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665168101621) 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, 2996252595 + ... + 2996252816.

It is an arithmetic number, because the mean of its divisors is an integer number (113857602828).

Almost surely, 2^665168100621 is an apocalyptic number.

It is an amenable number.

665168100621 is a deficient number, since it is larger than the sum of its proper divisors (245692722003).

665168100621 is a wasteful number, since it uses less digits than its factorization.

665168100621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5992505451.

The product of its (nonzero) digits is 103680, while the sum is 42.

The spelling of 665168100621 in words is "six hundred sixty-five billion, one hundred sixty-eight million, one hundred thousand, six hundred twenty-one".