665259680 has 48 divisors (see below), whose sum is σ = 1573375104. Its totient is φ = 265816320.

The previous prime is 665259677. The next prime is 665259689. The reversal of 665259680 is 86952566.

It is not an unprimeable number, because it can be changed into a prime (665259689) 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, 206885 + ... + 210075.

It is an arithmetic number, because the mean of its divisors is an integer number (32778648).

Almost surely, 2^665259680 is an apocalyptic number.

It is an amenable number.

665259680 is an abundant number, since it is smaller than the sum of its proper divisors (908115424).

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

665259680 is a wasteful number, since it uses less digits than its factorization.

665259680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4509 (or 4501 counting only the distinct ones).

The product of its (nonzero) digits is 777600, while the sum is 47.

The square root of 665259680 is about 25792.6284042554. The cubic root of 665259680 is about 872.9654738581.

The spelling of 665259680 in words is "six hundred sixty-five million, two hundred fifty-nine thousand, six hundred eighty".