138637739 has 2 divisors, whose sum is σ = 138637740. Its totient is φ = 138637738.

The previous prime is 138637729. The next prime is 138637783. The reversal of 138637739 is 937736831.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-138637739 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 138637693 and 138637702.

It is not a weakly prime, because it can be changed into another prime (138637729) 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, 69318869 + 69318870.

It is an arithmetic number, because the mean of its divisors is an integer number (69318870).

Almost surely, 2^138637739 is an apocalyptic number.

138637739 is a deficient number, since it is larger than the sum of its proper divisors (1).

138637739 is an equidigital number, since it uses as much as digits as its factorization.

138637739 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 571536, while the sum is 47.

The square root of 138637739 is about 11774.4528110651. The cubic root of 138637739 is about 517.5597435440.

The spelling of 138637739 in words is "one hundred thirty-eight million, six hundred thirty-seven thousand, seven hundred thirty-nine".