138778018 has 8 divisors (see below), whose sum is σ = 208220112. Its totient is φ = 69371316.

The previous prime is 138777983. The next prime is 138778049. The reversal of 138778018 is 810877831.

It is a happy number.

138778018 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5821 + ... + 17647.

It is an arithmetic number, because the mean of its divisors is an integer number (26027514).

Almost surely, 2^138778018 is an apocalyptic number.

138778018 is a deficient number, since it is larger than the sum of its proper divisors (69442094).

138778018 is a wasteful number, since it uses less digits than its factorization.

138778018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17696.

The product of its (nonzero) digits is 75264, while the sum is 43.

The square root of 138778018 is about 11780.4082272220. The cubic root of 138778018 is about 517.7342469900.

The spelling of 138778018 in words is "one hundred thirty-eight million, seven hundred seventy-eight thousand, eighteen".