665618518 has 16 divisors (see below), whose sum is σ = 1024143120. Its totient is φ = 324259200.

The previous prime is 665618509. The next prime is 665618579. The reversal of 665618518 is 815816566.

It is a congruent number.

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, 61498 + ... + 71506.

It is an arithmetic number, because the mean of its divisors is an integer number (64008945).

Almost surely, 2^665618518 is an apocalyptic number.

665618518 is a deficient number, since it is larger than the sum of its proper divisors (358524602).

665618518 is a wasteful number, since it uses less digits than its factorization.

665618518 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10863.

The product of its digits is 345600, while the sum is 46.

The square root of 665618518 is about 25799.5836788116. The cubic root of 665618518 is about 873.1224034946.

The spelling of 665618518 in words is "six hundred sixty-five million, six hundred eighteen thousand, five hundred eighteen".