138597973 has 2 divisors, whose sum is σ = 138597974. Its totient is φ = 138597972.

The previous prime is 138597961. The next prime is 138597997. The reversal of 138597973 is 379795831.

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., 134026929 + 4571044 = 11577^2 + 2138^2 .

It is an emirp because it is prime and its reverse (379795831) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 138597973 - 2⁵ = 138597941 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 138597973.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (138598973) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69298986 + 69298987.

It is an arithmetic number, because the mean of its divisors is an integer number (69298987).

Almost surely, 2^138597973 is an apocalyptic number.

It is an amenable number.

138597973 is a deficient number, since it is larger than the sum of its proper divisors (1).

138597973 is an equidigital number, since it uses as much as digits as its factorization.

138597973 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1428840, while the sum is 52.

The square root of 138597973 is about 11772.7640339896. The cubic root of 138597973 is about 517.5102542563.

The spelling of 138597973 in words is "one hundred thirty-eight million, five hundred ninety-seven thousand, nine hundred seventy-three".