640036780 has 24 divisors (see below), whose sum is σ = 1344622608. Its totient is φ = 255910848.

The previous prime is 640036777. The next prime is 640036781. The reversal of 640036780 is 87630046.

640036780 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (640036781) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 61302 + ... + 70978.

It is an arithmetic number, because the mean of its divisors is an integer number (56025942).

Almost surely, 2^640036780 is an apocalyptic number.

It is an amenable number.

640036780 is an abundant number, since it is smaller than the sum of its proper divisors (704585828).

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

640036780 is a wasteful number, since it uses less digits than its factorization.

640036780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12993 (or 12991 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 34.

The square root of 640036780 is about 25298.9481994805. The cubic root of 640036780 is about 861.7903840523.

The spelling of 640036780 in words is "six hundred forty million, thirty-six thousand, seven hundred eighty".