138478068 has 18 divisors (see below), whose sum is σ = 350041874. Its totient is φ = 46159344.

The previous prime is 138478063. The next prime is 138478097. The reversal of 138478068 is 860874831.

It can be written as a sum of positive squares in only one way, i.e., 129549924 + 8928144 = 11382^2 + 2988^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138478063) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1923271 + ... + 1923342.

Almost surely, 2^138478068 is an apocalyptic number.

138478068 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

138478068 is an abundant number, since it is smaller than the sum of its proper divisors (211563806).

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

138478068 is a wasteful number, since it uses less digits than its factorization.

138478068 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3846623 (or 3846618 counting only the distinct ones).

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

The square root of 138478068 is about 11767.6704576564. The cubic root of 138478068 is about 517.3609736460.

The spelling of 138478068 in words is "one hundred thirty-eight million, four hundred seventy-eight thousand, sixty-eight".