138394577 has 2 divisors, whose sum is σ = 138394578. Its totient is φ = 138394576.

The previous prime is 138394573. The next prime is 138394579. The reversal of 138394577 is 775493831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 136445761 + 1948816 = 11681^2 + 1396^2 .

It is a cyclic number.

It is not a de Polignac number, because 138394577 - 2² = 138394573 is a prime.

Together with 138394579, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (138394573) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69197288 + 69197289.

It is an arithmetic number, because the mean of its divisors is an integer number (69197289).

Almost surely, 2^138394577 is an apocalyptic number.

It is an amenable number.

138394577 is a deficient number, since it is larger than the sum of its proper divisors (1).

138394577 is an equidigital number, since it uses as much as digits as its factorization.

138394577 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 635040, while the sum is 47.

The square root of 138394577 is about 11764.1224492097. The cubic root of 138394577 is about 517.2569772284.

The spelling of 138394577 in words is "one hundred thirty-eight million, three hundred ninety-four thousand, five hundred seventy-seven".