138999397 has 2 divisors, whose sum is σ = 138999398. Its totient is φ = 138999396.

The previous prime is 138999347. The next prime is 138999409. The reversal of 138999397 is 793999831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 89000356 + 49999041 = 9434^2 + 7071^2 .

It is a cyclic number.

It is not a de Polignac number, because 138999397 - 2¹⁵ = 138966629 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (138999317) 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, 69499698 + 69499699.

It is an arithmetic number, because the mean of its divisors is an integer number (69499699).

Almost surely, 2^138999397 is an apocalyptic number.

It is an amenable number.

138999397 is a deficient number, since it is larger than the sum of its proper divisors (1).

138999397 is an equidigital number, since it uses as much as digits as its factorization.

138999397 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3306744, while the sum is 58.

The square root of 138999397 is about 11789.8005496276. The cubic root of 138999397 is about 518.0093976719.

The spelling of 138999397 in words is "one hundred thirty-eight million, nine hundred ninety-nine thousand, three hundred ninety-seven".