640332207 has 12 divisors (see below), whose sum is σ = 930036744. Its totient is φ = 424528560.

The previous prime is 640332197. The next prime is 640332239. The reversal of 640332207 is 702233046.

It is a de Polignac number, because none of the positive numbers 2^k-640332207 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640332257) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 194913 + ... + 198170.

It is an arithmetic number, because the mean of its divisors is an integer number (77503062).

Almost surely, 2^640332207 is an apocalyptic number.

640332207 is a deficient number, since it is larger than the sum of its proper divisors (289704537).

640332207 is a wasteful number, since it uses less digits than its factorization.

640332207 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 393270 (or 393267 counting only the distinct ones).

The product of its (nonzero) digits is 6048, while the sum is 27.

The square root of 640332207 is about 25304.7862468743. The cubic root of 640332207 is about 861.9229581969.

The spelling of 640332207 in words is "six hundred forty million, three hundred thirty-two thousand, two hundred seven".