640204677388 has 24 divisors (see below), whose sum is σ = 1132193538000. Its totient is φ = 316728030528.

The previous prime is 640204677347. The next prime is 640204677421. The reversal of 640204677388 is 883776402046.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 547363 + ... + 1256986.

It is an arithmetic number, because the mean of its divisors is an integer number (47174730750).

Almost surely, 2^640204677388 is an apocalyptic number.

It is an amenable number.

640204677388 is a deficient number, since it is larger than the sum of its proper divisors (491988860612).

640204677388 is a wasteful number, since it uses less digits than its factorization.

640204677388 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1805289 (or 1805287 counting only the distinct ones).

The product of its (nonzero) digits is 10838016, while the sum is 55.

The spelling of 640204677388 in words is "six hundred forty billion, two hundred four million, six hundred seventy-seven thousand, three hundred eighty-eight".