138628873 has 2 divisors, whose sum is σ = 138628874. Its totient is φ = 138628872.

The previous prime is 138628859. The next prime is 138628891. The reversal of 138628873 is 378826831.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 112954384 + 25674489 = 10628^2 + 5067^2 .

It is a cyclic number.

It is not a de Polignac number, because 138628873 - 2⁹ = 138628361 is a prime.

It is not a weakly prime, because it can be changed into another prime (138628823) 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, 69314436 + 69314437.

It is an arithmetic number, because the mean of its divisors is an integer number (69314437).

Almost surely, 2^138628873 is an apocalyptic number.

It is an amenable number.

138628873 is a deficient number, since it is larger than the sum of its proper divisors (1).

138628873 is an equidigital number, since it uses as much as digits as its factorization.

138628873 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 387072, while the sum is 46.

The square root of 138628873 is about 11774.0763119660. The cubic root of 138628873 is about 517.5487105152.

The spelling of 138628873 in words is "one hundred thirty-eight million, six hundred twenty-eight thousand, eight hundred seventy-three".