664722365 has 4 divisors (see below), whose sum is σ = 797666844. Its totient is φ = 531777888.

The previous prime is 664722347. The next prime is 664722419. The reversal of 664722365 is 563227466.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 366607609 + 298114756 = 19147^2 + 17266^2 .

It is a cyclic number.

It is not a de Polignac number, because 664722365 - 2¹⁰ = 664721341 is a prime.

It is a Duffinian number.

It is a Curzon number.

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, 66472232 + ... + 66472241.

It is an arithmetic number, because the mean of its divisors is an integer number (199416711).

Almost surely, 2^664722365 is an apocalyptic number.

It is an amenable number.

664722365 is a deficient number, since it is larger than the sum of its proper divisors (132944479).

664722365 is a wasteful number, since it uses less digits than its factorization.

664722365 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 132944478.

The product of its digits is 362880, while the sum is 41.

The square root of 664722365 is about 25782.2102427236. The cubic root of 664722365 is about 872.7303858182.

The spelling of 664722365 in words is "six hundred sixty-four million, seven hundred twenty-two thousand, three hundred sixty-five".