664722407 has 4 divisors (see below), whose sum is σ = 668436120. Its totient is φ = 661008696.

The previous prime is 664722347. The next prime is 664722419. The reversal of 664722407 is 704227466.

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

It is a cyclic number.

It is not a de Polignac number, because 664722407 - 2²⁶ = 597613543 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664722437) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1856588 + ... + 1856945.

It is an arithmetic number, because the mean of its divisors is an integer number (167109030).

Almost surely, 2^664722407 is an apocalyptic number.

664722407 is a deficient number, since it is larger than the sum of its proper divisors (3713713).

664722407 is a wasteful number, since it uses less digits than its factorization.

664722407 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3713712.

The product of its (nonzero) digits is 112896, while the sum is 38.

The square root of 664722407 is about 25782.2110572387. The cubic root of 664722407 is about 872.7304041992.

The spelling of 664722407 in words is "six hundred sixty-four million, seven hundred twenty-two thousand, four hundred seven".