138673637 has 2 divisors, whose sum is σ = 138673638. Its totient is φ = 138673636.

The previous prime is 138673589. The next prime is 138673687. The reversal of 138673637 is 736376831.

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., 113763556 + 24910081 = 10666^2 + 4991^2 .

It is an emirp because it is prime and its reverse (736376831) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 138673637 - 2¹⁰ = 138672613 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (138673687) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69336818 + 69336819.

It is an arithmetic number, because the mean of its divisors is an integer number (69336819).

Almost surely, 2^138673637 is an apocalyptic number.

It is an amenable number.

138673637 is a deficient number, since it is larger than the sum of its proper divisors (1).

138673637 is an equidigital number, since it uses as much as digits as its factorization.

138673637 is an evil number, because the sum of its binary digits is even.

The product of its digits is 381024, while the sum is 44.

The square root of 138673637 is about 11775.9771144479. The cubic root of 138673637 is about 517.6044109302.

The spelling of 138673637 in words is "one hundred thirty-eight million, six hundred seventy-three thousand, six hundred thirty-seven".