123131389 has 2 divisors, whose sum is σ = 123131390. Its totient is φ = 123131388.

The previous prime is 123131387. The next prime is 123131417. The reversal of 123131389 is 983131321.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 119727364 + 3404025 = 10942^2 + 1845^2 .

It is a cyclic number.

It is not a de Polignac number, because 123131389 - 2¹ = 123131387 is a prime.

It is a super-2 number, since 2×123131389² = 30322677914138642, which contains 22 as substring.

Together with 123131387, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 123131389.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (123131387) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61565694 + 61565695.

It is an arithmetic number, because the mean of its divisors is an integer number (61565695).

Almost surely, 2^123131389 is an apocalyptic number.

It is an amenable number.

123131389 is a deficient number, since it is larger than the sum of its proper divisors (1).

123131389 is an equidigital number, since it uses as much as digits as its factorization.

123131389 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3888, while the sum is 31.

The square root of 123131389 is about 11096.4583989668. The cubic root of 123131389 is about 497.4959995638.

The spelling of 123131389 in words is "one hundred twenty-three million, one hundred thirty-one thousand, three hundred eighty-nine".