664644763 has 8 divisors (see below), whose sum is σ = 670423040. Its totient is φ = 658881000.

The previous prime is 664644749. The next prime is 664644781. The reversal of 664644763 is 367446466.

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

It is a cyclic number.

It is not a de Polignac number, because 664644763 - 2¹³ = 664636571 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (664644713) 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, 101206 + ... + 107572.

It is an arithmetic number, because the mean of its divisors is an integer number (83802880).

Almost surely, 2^664644763 is an apocalyptic number.

664644763 is a deficient number, since it is larger than the sum of its proper divisors (5778277).

664644763 is a wasteful number, since it uses less digits than its factorization.

664644763 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7257.

The product of its digits is 1741824, while the sum is 46.

The square root of 664644763 is about 25780.7052463659. The cubic root of 664644763 is about 872.6964226367.

The spelling of 664644763 in words is "six hundred sixty-four million, six hundred forty-four thousand, seven hundred sixty-three".