138253873 has 2 divisors, whose sum is σ = 138253874. Its totient is φ = 138253872.

The previous prime is 138253859. The next prime is 138253879. The reversal of 138253873 is 378352831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 129686544 + 8567329 = 11388^2 + 2927^2 .

It is an emirp because it is prime and its reverse (378352831) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 138253873 - 2²¹ = 136156721 is a prime.

It is a super-2 number, since 2×138253873² = 38228266799000258, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (138253879) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69126936 + 69126937.

It is an arithmetic number, because the mean of its divisors is an integer number (69126937).

Almost surely, 2^138253873 is an apocalyptic number.

It is an amenable number.

138253873 is a deficient number, since it is larger than the sum of its proper divisors (1).

138253873 is an equidigital number, since it uses as much as digits as its factorization.

138253873 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 120960, while the sum is 40.

The square root of 138253873 is about 11758.1407118643. The cubic root of 138253873 is about 517.0816215988.

It can be divided in two parts, 1382 and 53873, that added together give a palindrome (55255).

The spelling of 138253873 in words is "one hundred thirty-eight million, two hundred fifty-three thousand, eight hundred seventy-three".