138903907 has 4 divisors (see below), whose sum is σ = 139136400. Its totient is φ = 138671416.

The previous prime is 138903899. The next prime is 138903917. The reversal of 138903907 is 709309831.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 138903907 - 2³ = 138903899 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 138903907.

It is not an unprimeable number, because it can be changed into a prime (138903917) 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 in 3 ways as a sum of consecutive naturals, for example, 115348 + ... + 116545.

It is an arithmetic number, because the mean of its divisors is an integer number (34784100).

Almost surely, 2^138903907 is an apocalyptic number.

138903907 is a deficient number, since it is larger than the sum of its proper divisors (232493).

138903907 is an equidigital number, since it uses as much as digits as its factorization.

138903907 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 232492.

The product of its (nonzero) digits is 40824, while the sum is 40.

The square root of 138903907 is about 11785.7501670449. The cubic root of 138903907 is about 517.8907495581.

The spelling of 138903907 in words is "one hundred thirty-eight million, nine hundred three thousand, nine hundred seven".