638881222 has 8 divisors (see below), whose sum is σ = 1095224976. Its totient is φ = 273806232.

The previous prime is 638881219. The next prime is 638881237. The reversal of 638881222 is 222188836.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22817173 + ... + 22817200.

It is an arithmetic number, because the mean of its divisors is an integer number (136903122).

Almost surely, 2^638881222 is an apocalyptic number.

638881222 is a deficient number, since it is larger than the sum of its proper divisors (456343754).

638881222 is a wasteful number, since it uses less digits than its factorization.

638881222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45634382.

The product of its digits is 73728, while the sum is 40.

The square root of 638881222 is about 25276.0998178121. The cubic root of 638881222 is about 861.2714301808.

The spelling of 638881222 in words is "six hundred thirty-eight million, eight hundred eighty-one thousand, two hundred twenty-two".