640933244 has 12 divisors (see below), whose sum is σ = 1281866544. Its totient is φ = 274685664.

The previous prime is 640933229. The next prime is 640933253. The reversal of 640933244 is 442339046.

640933244 is an admirable number.

It is a congruent number.

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, 11445209 + ... + 11445264.

It is an arithmetic number, because the mean of its divisors is an integer number (106822212).

Almost surely, 2^640933244 is an apocalyptic number.

It is an amenable number.

640933244 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

640933244 is a wasteful number, since it uses less digits than its factorization.

640933244 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22890484 (or 22890482 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 35.

The square root of 640933244 is about 25316.6594162816. The cubic root of 640933244 is about 862.1925503359.

The spelling of 640933244 in words is "six hundred forty million, nine hundred thirty-three thousand, two hundred forty-four".