665949580 has 24 divisors (see below), whose sum is σ = 1428251328. Its totient is φ = 260711808.

The previous prime is 665949553. The next prime is 665949623. The reversal of 665949580 is 85949566.

665949580 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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, 353289 + ... + 355168.

It is an arithmetic number, because the mean of its divisors is an integer number (59510472).

Almost surely, 2^665949580 is an apocalyptic number.

It is an amenable number.

665949580 is an abundant number, since it is smaller than the sum of its proper divisors (762301748).

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

665949580 is a wasteful number, since it uses less digits than its factorization.

665949580 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 708513 (or 708511 counting only the distinct ones).

The product of its (nonzero) digits is 2332800, while the sum is 52.

The square root of 665949580 is about 25805.9989149810. The cubic root of 665949580 is about 873.2671359157.

The spelling of 665949580 in words is "six hundred sixty-five million, nine hundred forty-nine thousand, five hundred eighty".