138426661815780 has 384 divisors, whose sum is σ = 438747489976320. Its totient is φ = 32388782469120.

The previous prime is 138426661815779. The next prime is 138426661815791. The reversal of 138426661815780 is 87518166624831.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 173994736 + ... + 174788504.

It is an arithmetic number, because the mean of its divisors is an integer number (1142571588480).

Almost surely, 2^{138426661815780} is an apocalyptic number.

138426661815780 is a gapful number since it is divisible by the number (10) 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 138426661815780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (219373744988160).

138426661815780 is an abundant number, since it is smaller than the sum of its proper divisors (300320828160540).

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

138426661815780 is a wasteful number, since it uses less digits than its factorization.

138426661815780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 793979 (or 793977 counting only the distinct ones).

The product of its (nonzero) digits is 92897280, while the sum is 66.

The spelling of 138426661815780 in words is "one hundred thirty-eight trillion, four hundred twenty-six billion, six hundred sixty-one million, eight hundred fifteen thousand, seven hundred eighty".