643488255138 has 32 divisors (see below), whose sum is σ = 1354969909440. Its totient is φ = 203168148480.

The previous prime is 643488255079. The next prime is 643488255167. The reversal of 643488255138 is 831552884346.

It is a Harshad number since it is a multiple of its sum of digits (57).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 67606 + ... + 1136462.

It is an arithmetic number, because the mean of its divisors is an integer number (42342809670).

Almost surely, 2^643488255138 is an apocalyptic number.

643488255138 is an abundant number, since it is smaller than the sum of its proper divisors (711481654302).

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

643488255138 is a wasteful number, since it uses less digits than its factorization.

643488255138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1074162.

The product of its digits is 22118400, while the sum is 57.

The spelling of 643488255138 in words is "six hundred forty-three billion, four hundred eighty-eight million, two hundred fifty-five thousand, one hundred thirty-eight".