640317456 has 60 divisors (see below), whose sum is σ = 1816577308. Its totient is φ = 210511872.

The previous prime is 640317443. The next prime is 640317473. The reversal of 640317456 is 654713046.

It is a happy number.

640317456 is a `hidden beast` number, since 640 + 3 + 1 + 7 + 4 + 5 + 6 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 116640000 + 523677456 = 10800^2 + 22884^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 640317456.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 19945 + ... + 40968.

Almost surely, 2^640317456 is an apocalyptic number.

It is an amenable number.

640317456 is an abundant number, since it is smaller than the sum of its proper divisors (1176259852).

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

640317456 is a wasteful number, since it uses less digits than its factorization.

640317456 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61000 (or 60991 counting only the distinct ones).

The product of its (nonzero) digits is 60480, while the sum is 36.

The square root of 640317456 is about 25304.4947785962. The cubic root of 640317456 is about 861.9163395891.

It can be divided in two parts, 640 and 317456, that added together give a square (318096 = 564²).

The spelling of 640317456 in words is "six hundred forty million, three hundred seventeen thousand, four hundred fifty-six".