138605377 has 2 divisors, whose sum is σ = 138605378. Its totient is φ = 138605376.

The previous prime is 138605287. The next prime is 138605417. The reversal of 138605377 is 773506831.

It is an a-pointer prime, because the next prime (138605417) can be obtained adding 138605377 to its sum of digits (40).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 99680256 + 38925121 = 9984^2 + 6239^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-138605377 is a prime.

It is a super-2 number, since 2×138605377² = 38422901066624258, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (138608377) 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, 69302688 + 69302689.

It is an arithmetic number, because the mean of its divisors is an integer number (69302689).

Almost surely, 2^138605377 is an apocalyptic number.

It is an amenable number.

138605377 is a deficient number, since it is larger than the sum of its proper divisors (1).

138605377 is an equidigital number, since it uses as much as digits as its factorization.

138605377 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 105840, while the sum is 40.

The square root of 138605377 is about 11773.0784844067. The cubic root of 138605377 is about 517.5194693446.

The spelling of 138605377 in words is "one hundred thirty-eight million, six hundred five thousand, three hundred seventy-seven".