638823858212 has 12 divisors (see below), whose sum is σ = 1118088844656. Its totient is φ = 319369902600.

The previous prime is 638823858163. The next prime is 638823858227. The reversal of 638823858212 is 212858328836.

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 3 ways as a sum of consecutive naturals, for example, 10472414 + ... + 10533237.

It is an arithmetic number, because the mean of its divisors is an integer number (93174070388).

Almost surely, 2^638823858212 is an apocalyptic number.

It is an amenable number.

638823858212 is a deficient number, since it is larger than the sum of its proper divisors (479264986444).

638823858212 is a wasteful number, since it uses less digits than its factorization.

638823858212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21013258 (or 21013256 counting only the distinct ones).

The product of its digits is 8847360, while the sum is 56.

The spelling of 638823858212 in words is "six hundred thirty-eight billion, eight hundred twenty-three million, eight hundred fifty-eight thousand, two hundred twelve".