640378558 has 16 divisors (see below), whose sum is σ = 1003428000. Its totient is φ = 305933056.

The previous prime is 640378547. The next prime is 640378591. The reversal of 640378558 is 855873046.

It is a Harshad number since it is a multiple of its sum of digits (46).

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 7 ways as a sum of consecutive naturals, for example, 37818 + ... + 52066.

It is an arithmetic number, because the mean of its divisors is an integer number (62714250).

Almost surely, 2^640378558 is an apocalyptic number.

640378558 is a deficient number, since it is larger than the sum of its proper divisors (363049442).

640378558 is a wasteful number, since it uses less digits than its factorization.

640378558 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15251.

The product of its (nonzero) digits is 806400, while the sum is 46.

The square root of 640378558 is about 25305.7020847081. The cubic root of 640378558 is about 861.9437547078.

The spelling of 640378558 in words is "six hundred forty million, three hundred seventy-eight thousand, five hundred fifty-eight".