18439229 has 2 divisors, whose sum is σ = 18439230. Its totient is φ = 18439228.

The previous prime is 18439219. The next prime is 18439231. The reversal of 18439229 is 92293481.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12264004 + 6175225 = 3502^2 + 2485^2 .

It is a cyclic number.

It is not a de Polignac number, because 18439229 - 2¹² = 18435133 is a prime.

It is a super-2 number, since 2×18439229² = 680010332228882, which contains 22 as substring.

Together with 18439231, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 18439192 and 18439201.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18439219) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9219614 + 9219615.

It is an arithmetic number, because the mean of its divisors is an integer number (9219615).

Almost surely, 2^18439229 is an apocalyptic number.

It is an amenable number.

18439229 is a deficient number, since it is larger than the sum of its proper divisors (1).

18439229 is an equidigital number, since it uses as much as digits as its factorization.

18439229 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 31104, while the sum is 38.

The square root of 18439229 is about 4294.0923371535. The cubic root of 18439229 is about 264.1887090091.

The spelling of 18439229 in words is "eighteen million, four hundred thirty-nine thousand, two hundred twenty-nine".