138591247878 has 48 divisors (see below), whose sum is σ = 301485505776. Its totient is φ = 46012147200.

The previous prime is 138591247877. The next prime is 138591247901. The reversal of 138591247878 is 878742195831.

138591247878 is a `hidden beast` number, since 1 + 3 + 8 + 5 + 91 + 2 + 478 + 78 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138591247871) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4669401 + ... + 4698987.

It is an arithmetic number, because the mean of its divisors is an integer number (6280948037).

Almost surely, 2^138591247878 is an apocalyptic number.

138591247878 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

138591247878 is an abundant number, since it is smaller than the sum of its proper divisors (162894257898).

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

138591247878 is a wasteful number, since it uses less digits than its factorization.

138591247878 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30629 (or 30626 counting only the distinct ones).

The product of its digits is 27095040, while the sum is 63.

The spelling of 138591247878 in words is "one hundred thirty-eight billion, five hundred ninety-one million, two hundred forty-seven thousand, eight hundred seventy-eight".