664634655 has 12 divisors (see below), whose sum is σ = 1152033480. Its totient is φ = 354471792.

The previous prime is 664634651. The next prime is 664634671. The reversal of 664634655 is 556436466.

664634655 is a `hidden beast` number, since 6 + 6 + 4 + 634 + 6 + 5 + 5 = 666.

It is not a de Polignac number, because 664634655 - 2² = 664634651 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45), and also a Moran number because the ratio is a prime number: 14769659 = 664634655 / (6 + 6 + 4 + 6 + 3 + 4 + 6 + 5 + 5).

It is a self number, because there is not a number n which added to its sum of digits gives 664634655.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664634651) by changing a digit.

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, 7384785 + ... + 7384874.

It is an arithmetic number, because the mean of its divisors is an integer number (96002790).

Almost surely, 2^664634655 is an apocalyptic number.

664634655 is a deficient number, since it is larger than the sum of its proper divisors (487398825).

664634655 is a wasteful number, since it uses less digits than its factorization.

664634655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14769670 (or 14769667 counting only the distinct ones).

The product of its digits is 1555200, while the sum is 45.

The square root of 664634655 is about 25780.5092075389. The cubic root of 664634655 is about 872.6919985891.

The spelling of 664634655 in words is "six hundred sixty-four million, six hundred thirty-four thousand, six hundred fifty-five".