138340042 has 16 divisors (see below), whose sum is σ = 216421632. Its totient is φ = 66245760.

The previous prime is 138340039. The next prime is 138340049. The reversal of 138340042 is 240043831.

It is a junction number, because it is equal to n+sod(n) for n = 138339989 and 138340016.

It is not an unprimeable number, because it can be changed into a prime (138340049) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5488 + ... + 17515.

It is an arithmetic number, because the mean of its divisors is an integer number (13526352).

Almost surely, 2^138340042 is an apocalyptic number.

138340042 is a deficient number, since it is larger than the sum of its proper divisors (78081590).

138340042 is a wasteful number, since it uses less digits than its factorization.

138340042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23133.

The product of its (nonzero) digits is 2304, while the sum is 25.

The square root of 138340042 is about 11761.8043683782. The cubic root of 138340042 is about 517.1890258295.

Adding to 138340042 its reverse (240043831), we get a palindrome (378383873).

The spelling of 138340042 in words is "one hundred thirty-eight million, three hundred forty thousand, forty-two".