138680805 has 32 divisors (see below), whose sum is σ = 228349440. Its totient is φ = 71830080.

The previous prime is 138680761. The next prime is 138680833. The reversal of 138680805 is 508086831.

It is a happy number.

It is not a de Polignac number, because 138680805 - 2⁹ = 138680293 is a prime.

It is a congruent number.

It is an unprimeable number.

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 in 31 ways as a sum of consecutive naturals, for example, 135586 + ... + 136604.

It is an arithmetic number, because the mean of its divisors is an integer number (7135920).

Almost surely, 2^138680805 is an apocalyptic number.

138680805 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

138680805 is a deficient number, since it is larger than the sum of its proper divisors (89668635).

138680805 is a wasteful number, since it uses less digits than its factorization.

138680805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1281.

The product of its (nonzero) digits is 46080, while the sum is 39.

The square root of 138680805 is about 11776.2814589326. The cubic root of 138680805 is about 517.6133290505.

The spelling of 138680805 in words is "one hundred thirty-eight million, six hundred eighty thousand, eight hundred five".