138395781440 has 112 divisors (see below), whose sum is σ = 398789298432. Its totient is φ = 44658794496.

The previous prime is 138395781439. The next prime is 138395781451. The reversal of 138395781440 is 44187593831.

It is a tau number, because it is divible by the number of its divisors (112).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1779092 + ... + 1855251.

It is an arithmetic number, because the mean of its divisors is an integer number (3560618736).

Almost surely, 2^138395781440 is an apocalyptic number.

138395781440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

138395781440 is an abundant number, since it is smaller than the sum of its proper divisors (260393516992).

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

138395781440 is a wasteful number, since it uses less digits than its factorization.

138395781440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3634384 (or 3634374 counting only the distinct ones).

The product of its (nonzero) digits is 2903040, while the sum is 53.

The spelling of 138395781440 in words is "one hundred thirty-eight billion, three hundred ninety-five million, seven hundred eighty-one thousand, four hundred forty".