638840568011520 has 576 divisors, whose sum is σ = 2504584494720000. Its totient is φ = 138335395774464.

The previous prime is 638840568011519. The next prime is 638840568011593. The reversal of 638840568011520 is 25110865048836.

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

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 12261376 + ... + 37789184.

It is an arithmetic number, because the mean of its divisors is an integer number (4348236970000).

Almost surely, 2^{638840568011520} is an apocalyptic number.

638840568011520 is a gapful number since it is divisible by the number (60) 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 638840568011520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1252292247360000).

638840568011520 is an abundant number, since it is smaller than the sum of its proper divisors (1865743926708480).

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

638840568011520 is a wasteful number, since it uses less digits than its factorization.

638840568011520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25527873 (or 25527845 counting only the distinct ones).

The product of its (nonzero) digits is 11059200, while the sum is 57.

The spelling of 638840568011520 in words is "six hundred thirty-eight trillion, eight hundred forty billion, five hundred sixty-eight million, eleven thousand, five hundred twenty".