664566505 has 8 divisors (see below), whose sum is σ = 816026112. Its totient is φ = 519289008.

The previous prime is 664566491. The next prime is 664566517. The reversal of 664566505 is 505665466.

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 664566505 - 2²³ = 656177897 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (43).

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1545289 + ... + 1545718.

It is an arithmetic number, because the mean of its divisors is an integer number (102003264).

Almost surely, 2^664566505 is an apocalyptic number.

It is an amenable number.

664566505 is a deficient number, since it is larger than the sum of its proper divisors (151459607).

664566505 is a wasteful number, since it uses less digits than its factorization.

664566505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3091055.

The product of its (nonzero) digits is 648000, while the sum is 43.

The square root of 664566505 is about 25779.1874387072. The cubic root of 664566505 is about 872.6621696737.

The spelling of 664566505 in words is "six hundred sixty-four million, five hundred sixty-six thousand, five hundred five".