138277897 has 2 divisors, whose sum is σ = 138277898. Its totient is φ = 138277896.

The previous prime is 138277873. The next prime is 138277921. The reversal of 138277897 is 798772831.

It is a balanced prime because it is at equal distance from previous prime (138277873) and next prime (138277921).

It can be written as a sum of positive squares in only one way, i.e., 132618256 + 5659641 = 11516^2 + 2379^2 .

It is an emirp because it is prime and its reverse (798772831) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 138277897 - 2¹¹ = 138275849 is a prime.

It is not a weakly prime, because it can be changed into another prime (138217897) 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, 69138948 + 69138949.

It is an arithmetic number, because the mean of its divisors is an integer number (69138949).

Almost surely, 2^138277897 is an apocalyptic number.

It is an amenable number.

138277897 is a deficient number, since it is larger than the sum of its proper divisors (1).

138277897 is an equidigital number, since it uses as much as digits as its factorization.

138277897 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1185408, while the sum is 52.

The square root of 138277897 is about 11759.1622575760. The cubic root of 138277897 is about 517.1115704871. Note that the first 3 decimals are identical.

The spelling of 138277897 in words is "one hundred thirty-eight million, two hundred seventy-seven thousand, eight hundred ninety-seven".