638355728884 has 48 divisors (see below), whose sum is σ = 1201028290560. Its totient is φ = 296132207360.

The previous prime is 638355728873. The next prime is 638355728887. The reversal of 638355728884 is 488827553836.

It is a super-3 number, since 3×638355728884³ (a number of 36 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638355728887) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 163437 + ... + 1141675.

It is an arithmetic number, because the mean of its divisors is an integer number (25021422720).

Almost surely, 2^638355728884 is an apocalyptic number.

It is an amenable number.

638355728884 is a deficient number, since it is larger than the sum of its proper divisors (562672561676).

638355728884 is a wasteful number, since it uses less digits than its factorization.

638355728884 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 978480 (or 978478 counting only the distinct ones).

The product of its digits is 309657600, while the sum is 67.

The spelling of 638355728884 in words is "six hundred thirty-eight billion, three hundred fifty-five million, seven hundred twenty-eight thousand, eight hundred eighty-four".