640126863 has 24 divisors (see below), whose sum is σ = 947288576. Its totient is φ = 416404800.

The previous prime is 640126829. The next prime is 640126871. The reversal of 640126863 is 368621046.

640126863 is a `hidden beast` number, since 640 + 1 + 2 + 6 + 8 + 6 + 3 = 666.

It is not a de Polignac number, because 640126863 - 2²⁰ = 639078287 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640126873) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 65133 + ... + 74313.

Almost surely, 2^640126863 is an apocalyptic number.

640126863 is a deficient number, since it is larger than the sum of its proper divisors (307161713).

640126863 is a wasteful number, since it uses less digits than its factorization.

640126863 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9375 (or 9372 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 36.

The square root of 640126863 is about 25300.7285072980. The cubic root of 640126863 is about 861.8308135108.

The spelling of 640126863 in words is "six hundred forty million, one hundred twenty-six thousand, eight hundred sixty-three".