138763917 has 12 divisors (see below), whose sum is σ = 200769660. Its totient is φ = 92355648.

The previous prime is 138763909. The next prime is 138763931. The reversal of 138763917 is 719367831.

138763917 is a `hidden beast` number, since 1 + 3 + 8 + 7 + 639 + 1 + 7 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 76842756 + 61921161 = 8766^2 + 7869^2 .

It is not a de Polignac number, because 138763917 - 2³ = 138763909 is a prime.

It is a super-2 number, since 2×138763917² = 38510849322365778, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138763907) 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 in 11 ways as a sum of consecutive naturals, for example, 6942 + ... + 18047.

It is an arithmetic number, because the mean of its divisors is an integer number (16730805).

Almost surely, 2^138763917 is an apocalyptic number.

It is an amenable number.

138763917 is a deficient number, since it is larger than the sum of its proper divisors (62005743).

138763917 is a wasteful number, since it uses less digits than its factorization.

138763917 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25612 (or 25609 counting only the distinct ones).

The product of its digits is 190512, while the sum is 45.

The square root of 138763917 is about 11779.8097183274. The cubic root of 138763917 is about 517.7167110286.

The spelling of 138763917 in words is "one hundred thirty-eight million, seven hundred sixty-three thousand, nine hundred seventeen".