18129613 has 2 divisors, whose sum is σ = 18129614. Its totient is φ = 18129612.

The previous prime is 18129581. The next prime is 18129653. The reversal of 18129613 is 31692181.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15350724 + 2778889 = 3918^2 + 1667^2 .

It is a cyclic number.

It is not a de Polignac number, because 18129613 - 2⁵ = 18129581 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18129653) 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 as a sum of consecutive naturals, namely, 9064806 + 9064807.

It is an arithmetic number, because the mean of its divisors is an integer number (9064807).

Almost surely, 2^18129613 is an apocalyptic number.

It is an amenable number.

18129613 is a deficient number, since it is larger than the sum of its proper divisors (1).

18129613 is an equidigital number, since it uses as much as digits as its factorization.

18129613 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2592, while the sum is 31.

The square root of 18129613 is about 4257.8883263890. Note that the first 3 decimals coincide. The cubic root of 18129613 is about 262.7016766087.

The spelling of 18129613 in words is "eighteen million, one hundred twenty-nine thousand, six hundred thirteen".