138896259840 has 540 divisors, whose sum is σ = 538235392464. Its totient is φ = 34185535488.

The previous prime is 138896259823. The next prime is 138896259847. The reversal of 138896259840 is 48952698831.

138896259840 is a `hidden beast` number, since 1 + 38 + 8 + 9 + 6 + 2 + 598 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (540).

It is not an unprimeable number, because it can be changed into a prime (138896259847) by changing a digit.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 17517957 + ... + 17525883.

Almost surely, 2^138896259840 is an apocalyptic number.

138896259840 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 138896259840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (269117696232).

138896259840 is an abundant number, since it is smaller than the sum of its proper divisors (399339132624).

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

138896259840 is an equidigital number, since it uses as much as digits as its factorization.

138896259840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7986 (or 7950 counting only the distinct ones).

The product of its (nonzero) digits is 29859840, while the sum is 63.

The spelling of 138896259840 in words is "one hundred thirty-eight billion, eight hundred ninety-six million, two hundred fifty-nine thousand, eight hundred forty".