138986437 has 2 divisors, whose sum is σ = 138986438. Its totient is φ = 138986436.

The previous prime is 138986417. The next prime is 138986443. The reversal of 138986437 is 734689831.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 138156516 + 829921 = 11754^2 + 911^2 .

It is an emirp because it is prime and its reverse (734689831) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-138986437 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (138986417) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69493218 + 69493219.

It is an arithmetic number, because the mean of its divisors is an integer number (69493219).

Almost surely, 2^138986437 is an apocalyptic number.

It is an amenable number.

138986437 is a deficient number, since it is larger than the sum of its proper divisors (1).

138986437 is an equidigital number, since it uses as much as digits as its factorization.

138986437 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 870912, while the sum is 49.

The square root of 138986437 is about 11789.2509091969. The cubic root of 138986437 is about 517.9932978168.

The spelling of 138986437 in words is "one hundred thirty-eight million, nine hundred eighty-six thousand, four hundred thirty-seven".