640854376 has 16 divisors (see below), whose sum is σ = 1224274500. Its totient is φ = 314381184.

The previous prime is 640854337. The next prime is 640854407. The reversal of 640854376 is 673458046.

It can be written as a sum of positive squares in 2 ways, for example, as 636552900 + 4301476 = 25230^2 + 2074^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 755301 + ... + 756148.

Almost surely, 2^640854376 is an apocalyptic number.

It is an amenable number.

640854376 is a deficient number, since it is larger than the sum of its proper divisors (583420124).

640854376 is a wasteful number, since it uses less digits than its factorization.

640854376 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1511508 (or 1511504 counting only the distinct ones).

The product of its (nonzero) digits is 483840, while the sum is 43.

The square root of 640854376 is about 25315.1017378955. The cubic root of 640854376 is about 862.1571840987.

The spelling of 640854376 in words is "six hundred forty million, eight hundred fifty-four thousand, three hundred seventy-six".