138867497 has 2 divisors, whose sum is σ = 138867498. Its totient is φ = 138867496.

The previous prime is 138867433. The next prime is 138867499. The reversal of 138867497 is 794768831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 70375321 + 68492176 = 8389^2 + 8276^2 .

It is a cyclic number.

It is not a de Polignac number, because 138867497 - 2⁶ = 138867433 is a prime.

Together with 138867499, 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 (138867499) 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, 69433748 + 69433749.

It is an arithmetic number, because the mean of its divisors is an integer number (69433749).

Almost surely, 2^138867497 is an apocalyptic number.

It is an amenable number.

138867497 is a deficient number, since it is larger than the sum of its proper divisors (1).

138867497 is an equidigital number, since it uses as much as digits as its factorization.

138867497 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2032128, while the sum is 53.

The square root of 138867497 is about 11784.2054038446. The cubic root of 138867497 is about 517.8454951315.

The spelling of 138867497 in words is "one hundred thirty-eight million, eight hundred sixty-seven thousand, four hundred ninety-seven".