640903340 has 72 divisors (see below), whose sum is σ = 1707994512. Its totient is φ = 199758720.

The previous prime is 640903339. The next prime is 640903411. The reversal of 640903340 is 43309046.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 18947 + ... + 40506.

It is an arithmetic number, because the mean of its divisors is an integer number (23722146).

Almost surely, 2^640903340 is an apocalyptic number.

It is an amenable number.

640903340 is an abundant number, since it is smaller than the sum of its proper divisors (1067091172).

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

640903340 is a wasteful number, since it uses less digits than its factorization.

640903340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59487 (or 59478 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 29.

The square root of 640903340 is about 25316.0688101451. The cubic root of 640903340 is about 862.1791410314.

The spelling of 640903340 in words is "six hundred forty million, nine hundred three thousand, three hundred forty".