647664523 has 8 divisors (see below), whose sum is σ = 711627840. Its totient is φ = 584548680.

The previous prime is 647664509. The next prime is 647664527. The reversal of 647664523 is 325466746.

647664523 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-647664523 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 647664523.

It is not an unprimeable number, because it can be changed into a prime (647664527) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 210265 + ... + 213322.

It is an arithmetic number, because the mean of its divisors is an integer number (88953480).

Almost surely, 2^647664523 is an apocalyptic number.

647664523 is a deficient number, since it is larger than the sum of its proper divisors (63963317).

647664523 is a wasteful number, since it uses less digits than its factorization.

647664523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 423737.

The product of its digits is 725760, while the sum is 43.

The square root of 647664523 is about 25449.2538790433. The cubic root of 647664523 is about 865.2003825919.

The spelling of 647664523 in words is "six hundred forty-seven million, six hundred sixty-four thousand, five hundred twenty-three".