138893878 has 8 divisors (see below), whose sum is σ = 208391040. Its totient is φ = 69430200.

The previous prime is 138893813. The next prime is 138893899. The reversal of 138893878 is 878398831.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10603 + ... + 19753.

It is an arithmetic number, because the mean of its divisors is an integer number (26048880).

Almost surely, 2^138893878 is an apocalyptic number.

138893878 is a deficient number, since it is larger than the sum of its proper divisors (69497162).

138893878 is an equidigital number, since it uses as much as digits as its factorization.

138893878 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16742.

The product of its digits is 2322432, while the sum is 55.

The square root of 138893878 is about 11785.3246879329. The cubic root of 138893878 is about 517.8782851827.

It can be divided in two parts, 1388 and 93878, that added together give a triangular number (95266 = T₄₃₆).

The spelling of 138893878 in words is "one hundred thirty-eight million, eight hundred ninety-three thousand, eight hundred seventy-eight".