138444787 has 16 divisors (see below), whose sum is σ = 162140832. Its totient is φ = 117020160.

The previous prime is 138444769. The next prime is 138444793. The reversal of 138444787 is 787444831.

It is a cyclic number.

It is not a de Polignac number, because 138444787 - 2¹⁹ = 137920499 is a prime.

It is not an unprimeable number, because it can be changed into a prime (138444707) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 289 + ... + 16642.

It is an arithmetic number, because the mean of its divisors is an integer number (10133802).

Almost surely, 2^138444787 is an apocalyptic number.

138444787 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

138444787 is a deficient number, since it is larger than the sum of its proper divisors (23696045).

138444787 is a wasteful number, since it uses less digits than its factorization.

138444787 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16998.

The product of its digits is 602112, while the sum is 46.

The square root of 138444787 is about 11766.2562865170. The cubic root of 138444787 is about 517.3195238329.

The spelling of 138444787 in words is "one hundred thirty-eight million, four hundred forty-four thousand, seven hundred eighty-seven".