640665314 has 8 divisors (see below), whose sum is σ = 961186908. Its totient is φ = 320269680.

The previous prime is 640665307. The next prime is 640665331. The reversal of 640665314 is 413566046.

It can be written as a sum of positive squares in 2 ways, for example, as 550700089 + 89965225 = 23467^2 + 9485^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17537 + ... + 39860.

Almost surely, 2^640665314 is an apocalyptic number.

640665314 is a deficient number, since it is larger than the sum of its proper divisors (320521594).

640665314 is a wasteful number, since it uses less digits than its factorization.

640665314 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 62980.

The product of its (nonzero) digits is 51840, while the sum is 35.

The square root of 640665314 is about 25311.3672882363. The cubic root of 640665314 is about 862.0723925040.

The spelling of 640665314 in words is "six hundred forty million, six hundred sixty-five thousand, three hundred fourteen".