138068478 has 48 divisors (see below), whose sum is σ = 325774800. Its totient is φ = 42094080.

The previous prime is 138068467. The next prime is 138068501. The reversal of 138068478 is 874860831.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2958 + ... + 16878.

It is an arithmetic number, because the mean of its divisors is an integer number (6786975).

Almost surely, 2^138068478 is an apocalyptic number.

138068478 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 138068478, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (162887400).

138068478 is an abundant number, since it is smaller than the sum of its proper divisors (187706322).

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

138068478 is a wasteful number, since it uses less digits than its factorization.

138068478 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13977 (or 13974 counting only the distinct ones).

The product of its (nonzero) digits is 258048, while the sum is 45.

The square root of 138068478 is about 11750.2543802251. The cubic root of 138068478 is about 516.8503870164.

The spelling of 138068478 in words is "one hundred thirty-eight million, sixty-eight thousand, four hundred seventy-eight".