665105656 has 16 divisors (see below), whose sum is σ = 1250611200. Its totient is φ = 331609344.

The previous prime is 665105647. The next prime is 665105663. The reversal of 665105656 is 656501566.

It is a congruent number.

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, 114936 + ... + 120583.

It is an arithmetic number, because the mean of its divisors is an integer number (78163200).

Almost surely, 2^665105656 is an apocalyptic number.

It is an amenable number.

665105656 is a deficient number, since it is larger than the sum of its proper divisors (585505544).

665105656 is a wasteful number, since it uses less digits than its factorization.

665105656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 235878 (or 235874 counting only the distinct ones).

The product of its (nonzero) digits is 162000, while the sum is 40.

The square root of 665105656 is about 25789.6424170635. The cubic root of 665105656 is about 872.8980976559.

The spelling of 665105656 in words is "six hundred sixty-five million, one hundred five thousand, six hundred fifty-six".