665656506 has 24 divisors (see below), whose sum is σ = 1444609920. Its totient is φ = 221523336.

The previous prime is 665656493. The next prime is 665656567. The reversal of 665656506 is 605656566.

It is a Curzon 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 11 ways as a sum of consecutive naturals, for example, 18730 + ... + 41013.

It is an arithmetic number, because the mean of its divisors is an integer number (60192080).

Almost surely, 2^665656506 is an apocalyptic number.

665656506 is an abundant number, since it is smaller than the sum of its proper divisors (778953414).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

665656506 is a wasteful number, since it uses less digits than its factorization.

665656506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60370 (or 60367 counting only the distinct ones).

The product of its (nonzero) digits is 972000, while the sum is 45.

The square root of 665656506 is about 25800.3198817379. The cubic root of 665656506 is about 873.1390133804.

The spelling of 665656506 in words is "six hundred sixty-five million, six hundred fifty-six thousand, five hundred six".