665213564 has 12 divisors (see below), whose sum is σ = 1165202304. Its totient is φ = 332298624.

The previous prime is 665213539. The next prime is 665213609. The reversal of 665213564 is 465312566.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 72149 + ... + 80844.

It is an arithmetic number, because the mean of its divisors is an integer number (97100192).

Almost surely, 2^665213564 is an apocalyptic number.

It is an amenable number.

665213564 is a deficient number, since it is larger than the sum of its proper divisors (499988740).

665213564 is a wasteful number, since it uses less digits than its factorization.

665213564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 154084 (or 154082 counting only the distinct ones).

The product of its digits is 129600, while the sum is 38.

The square root of 665213564 is about 25791.7344124043. The cubic root of 665213564 is about 872.9453019828.

The spelling of 665213564 in words is "six hundred sixty-five million, two hundred thirteen thousand, five hundred sixty-four".