138255938 has 4 divisors (see below), whose sum is σ = 207383910. Its totient is φ = 69127968.

The previous prime is 138255937. The next prime is 138255947. The reversal of 138255938 is 839552831.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 116791249 + 21464689 = 10807^2 + 4633^2 .

It is a super-2 number, since 2×138255938² = 38229408784519688, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (138255937) 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, 34563983 + ... + 34563986.

Almost surely, 2^138255938 is an apocalyptic number.

138255938 is a deficient number, since it is larger than the sum of its proper divisors (69127972).

138255938 is an equidigital number, since it uses as much as digits as its factorization.

138255938 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69127971.

The product of its digits is 259200, while the sum is 44.

The square root of 138255938 is about 11758.2285230387. The cubic root of 138255938 is about 517.0841960131.

The spelling of 138255938 in words is "one hundred thirty-eight million, two hundred fifty-five thousand, nine hundred thirty-eight".