640832507 has 4 divisors (see below), whose sum is σ = 732380016. Its totient is φ = 549285000.

The previous prime is 640832497. The next prime is 640832519. The reversal of 640832507 is 705238046.

It is a happy number.

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 640832507 - 2⁶ = 640832443 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (640832557) 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, 45773744 + ... + 45773757.

It is an arithmetic number, because the mean of its divisors is an integer number (183095004).

Almost surely, 2^640832507 is an apocalyptic number.

640832507 is a deficient number, since it is larger than the sum of its proper divisors (91547509).

640832507 is an equidigital number, since it uses as much as digits as its factorization.

640832507 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91547508.

The product of its (nonzero) digits is 40320, while the sum is 35.

The square root of 640832507 is about 25314.6697983600. The cubic root of 640832507 is about 862.1473770189.

The spelling of 640832507 in words is "six hundred forty million, eight hundred thirty-two thousand, five hundred seven".