665623108 has 12 divisors (see below), whose sum is σ = 1167748092. Its totient is φ = 331980800.

The previous prime is 665623099. The next prime is 665623141. The reversal of 665623108 is 801326566.

It can be written as a sum of positive squares in 2 ways, for example, as 650862144 + 14760964 = 25512^2 + 3842^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 205885 + ... + 209092.

It is an arithmetic number, because the mean of its divisors is an integer number (97312341).

Almost surely, 2^665623108 is an apocalyptic number.

It is an amenable number.

665623108 is a deficient number, since it is larger than the sum of its proper divisors (502124984).

665623108 is a wasteful number, since it uses less digits than its factorization.

665623108 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 415382 (or 415380 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 37.

The square root of 665623108 is about 25799.6726335820. The cubic root of 665623108 is about 873.1244104613.

The spelling of 665623108 in words is "six hundred sixty-five million, six hundred twenty-three thousand, one hundred eight".