138731518 has 8 divisors (see below), whose sum is σ = 208435320. Its totient is φ = 69253080.

The previous prime is 138731501. The next prime is 138731519. The reversal of 138731518 is 815137831.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138731519) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 54793 + ... + 57268.

It is an arithmetic number, because the mean of its divisors is an integer number (26054415).

Almost surely, 2^138731518 is an apocalyptic number.

138731518 is a deficient number, since it is larger than the sum of its proper divisors (69703802).

138731518 is a wasteful number, since it uses less digits than its factorization.

138731518 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 112682.

The product of its digits is 20160, while the sum is 37.

The square root of 138731518 is about 11778.4344460544. The cubic root of 138731518 is about 517.6764152282.

The spelling of 138731518 in words is "one hundred thirty-eight million, seven hundred thirty-one thousand, five hundred eighteen".