138822217 has 4 divisors (see below), whose sum is σ = 143609220. Its totient is φ = 134035216.

The previous prime is 138822199. The next prime is 138822259. The reversal of 138822217 is 712228831.

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

It can be written as a sum of positive squares in 2 ways, for example, as 91087936 + 47734281 = 9544^2 + 6909^2 .

It is not a de Polignac number, because 138822217 - 2²³ = 130433609 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138822287) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2393458 + ... + 2393515.

It is an arithmetic number, because the mean of its divisors is an integer number (35902305).

Almost surely, 2^138822217 is an apocalyptic number.

It is an amenable number.

138822217 is a deficient number, since it is larger than the sum of its proper divisors (4787003).

138822217 is an equidigital number, since it uses as much as digits as its factorization.

138822217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4787002.

The product of its digits is 10752, while the sum is 34.

The square root of 138822217 is about 11782.2840315450. The cubic root of 138822217 is about 517.7892050383.

The spelling of 138822217 in words is "one hundred thirty-eight million, eight hundred twenty-two thousand, two hundred seventeen".