665660450806 has 32 divisors (see below), whose sum is σ = 1076681739168. Its totient is φ = 306832700160.

The previous prime is 665660450801. The next prime is 665660450881. The reversal of 665660450806 is 608054066566.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665660450801) 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, 134284480 + ... + 134289436.

It is an arithmetic number, because the mean of its divisors is an integer number (33646304349).

Almost surely, 2^665660450806 is an apocalyptic number.

665660450806 is a deficient number, since it is larger than the sum of its proper divisors (411021288362).

665660450806 is a wasteful number, since it uses less digits than its factorization.

665660450806 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10576.

The product of its (nonzero) digits is 6220800, while the sum is 52.

The spelling of 665660450806 in words is "six hundred sixty-five billion, six hundred sixty million, four hundred fifty thousand, eight hundred six".