640907316 has 240 divisors, whose sum is σ = 2049062400. Its totient is φ = 170620992.

The previous prime is 640907261. The next prime is 640907339. The reversal of 640907316 is 613709046.

640907316 is a `hidden beast` number, since 640 + 9 + 0 + 7 + 3 + 1 + 6 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 4610775 + ... + 4610913.

It is an arithmetic number, because the mean of its divisors is an integer number (8537760).

Almost surely, 2^640907316 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 640907316, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1024531200).

640907316 is an abundant number, since it is smaller than the sum of its proper divisors (1408155084).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

640907316 is a wasteful number, since it uses less digits than its factorization.

640907316 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 288 (or 277 counting only the distinct ones).

The product of its (nonzero) digits is 27216, while the sum is 36.

The square root of 640907316 is about 25316.1473372233. The cubic root of 640907316 is about 862.1809239405.

The spelling of 640907316 in words is "six hundred forty million, nine hundred seven thousand, three hundred sixteen".