138743240 has 16 divisors (see below), whose sum is σ = 312172380. Its totient is φ = 55497280.

The previous prime is 138743233. The next prime is 138743243. The reversal of 138743240 is 42347831.

138743240 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 131377444 + 7365796 = 11462^2 + 2714^2 .

It is a junction number, because it is equal to n+sod(n) for n = 138743197 and 138743206.

It is not an unprimeable number, because it can be changed into a prime (138743243) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1734251 + ... + 1734330.

Almost surely, 2^138743240 is an apocalyptic number.

138743240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

138743240 is an abundant number, since it is smaller than the sum of its proper divisors (173429140).

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

138743240 is a wasteful number, since it uses less digits than its factorization.

138743240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3468592 (or 3468588 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 32.

The square root of 138743240 is about 11778.9320398753. The cubic root of 138743240 is about 517.6909950250.

The spelling of 138743240 in words is "one hundred thirty-eight million, seven hundred forty-three thousand, two hundred forty".