647665556 has 12 divisors (see below), whose sum is σ = 1182693792. Its totient is φ = 309753048.

The previous prime is 647665537. The next prime is 647665607. The reversal of 647665556 is 655566746.

647665556 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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, 3519830 + ... + 3520013.

It is an arithmetic number, because the mean of its divisors is an integer number (98557816).

Almost surely, 2^647665556 is an apocalyptic number.

It is an amenable number.

647665556 is a deficient number, since it is larger than the sum of its proper divisors (535028236).

647665556 is a wasteful number, since it uses less digits than its factorization.

647665556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7039870 (or 7039868 counting only the distinct ones).

The product of its digits is 4536000, while the sum is 50.

The square root of 647665556 is about 25449.2741743257. The cubic root of 647665556 is about 865.2008425788.

The spelling of 647665556 in words is "six hundred forty-seven million, six hundred sixty-five thousand, five hundred fifty-six".