640433677368 has 16 divisors (see below), whose sum is σ = 1601084193480. Its totient is φ = 213477892448.

The previous prime is 640433677349. The next prime is 640433677381. The reversal of 640433677368 is 863776334046.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13342368255 + ... + 13342368302.

Almost surely, 2^640433677368 is an apocalyptic number.

It is an amenable number.

640433677368 is an abundant number, since it is smaller than the sum of its proper divisors (960650516112).

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

640433677368 is a wasteful number, since it uses less digits than its factorization.

640433677368 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26684736566 (or 26684736562 counting only the distinct ones).

The product of its (nonzero) digits is 36578304, while the sum is 57.

The spelling of 640433677368 in words is "six hundred forty billion, four hundred thirty-three million, six hundred seventy-seven thousand, three hundred sixty-eight".