138838969 has 2 divisors, whose sum is σ = 138838970. Its totient is φ = 138838968.

The previous prime is 138838963. The next prime is 138838981. The reversal of 138838969 is 969838831.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 125148969 + 13690000 = 11187^2 + 3700^2 .

It is a cyclic number.

It is not a de Polignac number, because 138838969 - 2⁵ = 138838937 is a prime.

It is a super-2 number, since 2×138838969² = 38552518625965922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (138838963) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69419484 + 69419485.

It is an arithmetic number, because the mean of its divisors is an integer number (69419485).

Almost surely, 2^138838969 is an apocalyptic number.

It is an amenable number.

138838969 is a deficient number, since it is larger than the sum of its proper divisors (1).

138838969 is an equidigital number, since it uses as much as digits as its factorization.

138838969 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2239488, while the sum is 55.

The square root of 138838969 is about 11782.9949079171. The cubic root of 138838969 is about 517.8100318101.

The spelling of 138838969 in words is "one hundred thirty-eight million, eight hundred thirty-eight thousand, nine hundred sixty-nine".