640302321 has 8 divisors (see below), whose sum is σ = 853915104. Its totient is φ = 426778880.

The previous prime is 640302301. The next prime is 640302323. The reversal of 640302321 is 123203046.

It is a happy number.

640302321 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 640302321 - 2¹⁰ = 640301297 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (640302323) 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, 3291 + ... + 35936.

It is an arithmetic number, because the mean of its divisors is an integer number (106739388).

Almost surely, 2^640302321 is an apocalyptic number.

It is an amenable number.

640302321 is a deficient number, since it is larger than the sum of its proper divisors (213612783).

640302321 is a wasteful number, since it uses less digits than its factorization.

640302321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44671.

The product of its (nonzero) digits is 864, while the sum is 21.

The square root of 640302321 is about 25304.1957192873. The cubic root of 640302321 is about 861.9095485792.

Adding to 640302321 its reverse (123203046), we get a palindrome (763505367).

The spelling of 640302321 in words is "six hundred forty million, three hundred two thousand, three hundred twenty-one".