665757550 has 24 divisors (see below), whose sum is σ = 1278257472. Its totient is φ = 257712000.

The previous prime is 665757541. The next prime is 665757571. The reversal of 665757550 is 55757566.

It is a self number, because there is not a number n which added to its sum of digits gives 665757550.

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 11 ways as a sum of consecutive naturals, for example, 213211 + ... + 216310.

It is an arithmetic number, because the mean of its divisors is an integer number (53260728).

Almost surely, 2^665757550 is an apocalyptic number.

665757550 is a deficient number, since it is larger than the sum of its proper divisors (612499922).

665757550 is a wasteful number, since it uses less digits than its factorization.

665757550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 429564 (or 429559 counting only the distinct ones).

The product of its (nonzero) digits is 1102500, while the sum is 46.

The square root of 665757550 is about 25802.2780002077. The cubic root of 665757550 is about 873.1831908173.

The spelling of 665757550 in words is "six hundred sixty-five million, seven hundred fifty-seven thousand, five hundred fifty".