664228407 has 4 divisors (see below), whose sum is σ = 885637880. Its totient is φ = 442818936.

The previous prime is 664228373. The next prime is 664228417. The reversal of 664228407 is 704822466.

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

It is not a de Polignac number, because 664228407 - 2⁶ = 664228343 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664228417) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 110704732 + ... + 110704737.

It is an arithmetic number, because the mean of its divisors is an integer number (221409470).

Almost surely, 2^664228407 is an apocalyptic number.

664228407 is a deficient number, since it is larger than the sum of its proper divisors (221409473).

664228407 is a wasteful number, since it uses less digits than its factorization.

664228407 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 221409472.

The product of its (nonzero) digits is 129024, while the sum is 39.

The square root of 664228407 is about 25772.6290277108. The cubic root of 664228407 is about 872.5141557023.

The spelling of 664228407 in words is "six hundred sixty-four million, two hundred twenty-eight thousand, four hundred seven".