138361243 has 2 divisors, whose sum is σ = 138361244. Its totient is φ = 138361242.

The previous prime is 138361199. The next prime is 138361259. The reversal of 138361243 is 342163831.

It is a strong prime.

It is an emirp because it is prime and its reverse (342163831) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 138361243 - 2⁹ = 138360731 is a prime.

It is not a weakly prime, because it can be changed into another prime (138361043) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69180621 + 69180622.

It is an arithmetic number, because the mean of its divisors is an integer number (69180622).

Almost surely, 2^138361243 is an apocalyptic number.

138361243 is a deficient number, since it is larger than the sum of its proper divisors (1).

138361243 is an equidigital number, since it uses as much as digits as its factorization.

138361243 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10368, while the sum is 31.

The square root of 138361243 is about 11762.7055986282. The cubic root of 138361243 is about 517.2154447036.

It can be divided in two parts, 1383 and 61243, that added together give a palindrome (62626).

The spelling of 138361243 in words is "one hundred thirty-eight million, three hundred sixty-one thousand, two hundred forty-three".