638092836864 has 684 divisors, whose sum is σ = 2228907614544. Its totient is φ = 178872385536.

The previous prime is 638092836841. The next prime is 638092836959. The reversal of 638092836864 is 468638290836.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 12039487462 + ... + 12039487514.

Almost surely, 2^638092836864 is an apocalyptic number.

638092836864 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 638092836864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1114453807272).

638092836864 is an abundant number, since it is smaller than the sum of its proper divisors (1590814777680).

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

638092836864 is an frugal number, since it uses more digits than its factorization.

638092836864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 120 (or 65 counting only the distinct ones).

The product of its (nonzero) digits is 71663616, while the sum is 63.

The spelling of 638092836864 in words is "six hundred thirty-eight billion, ninety-two million, eight hundred thirty-six thousand, eight hundred sixty-four".