138831386 has 8 divisors (see below), whose sum is σ = 208313364. Its totient is φ = 69393600.

The previous prime is 138831383. The next prime is 138831389. The reversal of 138831386 is 683138831.

It is an interprime number because it is at equal distance from previous prime (138831383) and next prime (138831389).

It can be written as a sum of positive squares in 2 ways, for example, as 105987025 + 32844361 = 10295^2 + 5731^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (138831383) 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, 1565 + ... + 16736.

Almost surely, 2^138831386 is an apocalyptic number.

138831386 is a deficient number, since it is larger than the sum of its proper divisors (69481978).

138831386 is a wasteful number, since it uses less digits than its factorization.

138831386 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22096.

The product of its digits is 82944, while the sum is 41.

The square root of 138831386 is about 11782.6731262477. The cubic root of 138831386 is about 517.8006045218.

The spelling of 138831386 in words is "one hundred thirty-eight million, eight hundred thirty-one thousand, three hundred eighty-six".