665663488645 has 32 divisors (see below), whose sum is σ = 877598426880. Its totient is φ = 482911004160.

The previous prime is 665663488639. The next prime is 665663488657. The reversal of 665663488645 is 546884366566.

It is not a de Polignac number, because 665663488645 - 2⁵ = 665663488613 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1405849 + ... + 1818718.

It is an arithmetic number, because the mean of its divisors is an integer number (27424950840).

Almost surely, 2^665663488645 is an apocalyptic number.

It is an amenable number.

665663488645 is a deficient number, since it is larger than the sum of its proper divisors (211934938235).

665663488645 is a wasteful number, since it uses less digits than its factorization.

665663488645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3224685.

The product of its digits is 597196800, while the sum is 67.

The spelling of 665663488645 in words is "six hundred sixty-five billion, six hundred sixty-three million, four hundred eighty-eight thousand, six hundred forty-five".