138281243 has 2 divisors, whose sum is σ = 138281244. Its totient is φ = 138281242.

The previous prime is 138281207. The next prime is 138281257. The reversal of 138281243 is 342182831.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 138281243 - 2¹² = 138277147 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (138281203) by changing a digit.

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 as a sum of consecutive naturals, namely, 69140621 + 69140622.

It is an arithmetic number, because the mean of its divisors is an integer number (69140622).

Almost surely, 2^138281243 is an apocalyptic number.

138281243 is a deficient number, since it is larger than the sum of its proper divisors (1).

138281243 is an equidigital number, since it uses as much as digits as its factorization.

138281243 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9216, while the sum is 32.

The square root of 138281243 is about 11759.3045287551. The cubic root of 138281243 is about 517.1157414149.

The spelling of 138281243 in words is "one hundred thirty-eight million, two hundred eighty-one thousand, two hundred forty-three".