665239336880 has 40 divisors (see below), whose sum is σ = 1584405404064. Its totient is φ = 259605593600.

The previous prime is 665239336877. The next prime is 665239336967. The reversal of 665239336880 is 88633932566.

It is a tau number, because it is divible by the number of its divisors (40).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 101405156 + ... + 101411715.

Almost surely, 2^665239336880 is an apocalyptic number.

It is an amenable number.

665239336880 is an abundant number, since it is smaller than the sum of its proper divisors (919166067184).

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

665239336880 is a wasteful number, since it uses less digits than its factorization.

665239336880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 202816925 (or 202816919 counting only the distinct ones).

The product of its (nonzero) digits is 33592320, while the sum is 59.

The spelling of 665239336880 in words is "six hundred sixty-five billion, two hundred thirty-nine million, three hundred thirty-six thousand, eight hundred eighty".