18956489 has 2 divisors, whose sum is σ = 18956490. Its totient is φ = 18956488.

The previous prime is 18956467. The next prime is 18956491. The reversal of 18956489 is 98465981.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18490000 + 466489 = 4300^2 + 683^2 .

It is an emirp because it is prime and its reverse (98465981) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18956489 - 2¹⁶ = 18890953 is a prime.

Together with 18956491, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (18956449) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9478244 + 9478245.

It is an arithmetic number, because the mean of its divisors is an integer number (9478245).

Almost surely, 2^18956489 is an apocalyptic number.

It is an amenable number.

18956489 is a deficient number, since it is larger than the sum of its proper divisors (1).

18956489 is an equidigital number, since it uses as much as digits as its factorization.

18956489 is an evil number, because the sum of its binary digits is even.

The product of its digits is 622080, while the sum is 50.

The square root of 18956489 is about 4353.9050288218. The cubic root of 18956489 is about 266.6363165112.

The spelling of 18956489 in words is "eighteen million, nine hundred fifty-six thousand, four hundred eighty-nine".