18839969 has 2 divisors, whose sum is σ = 18839970. Its totient is φ = 18839968.

The previous prime is 18839941. The next prime is 18839981. The reversal of 18839969 is 96993881.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17181025 + 1658944 = 4145^2 + 1288^2 .

It is a cyclic number.

It is not a de Polignac number, because 18839969 - 2⁸ = 18839713 is a prime.

It is a super-2 number, since 2×18839969² = 709888863841922, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18839969.

It is not a weakly prime, because it can be changed into another prime (18838969) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9419984 + 9419985.

It is an arithmetic number, because the mean of its divisors is an integer number (9419985).

Almost surely, 2^18839969 is an apocalyptic number.

It is an amenable number.

18839969 is a deficient number, since it is larger than the sum of its proper divisors (1).

18839969 is an equidigital number, since it uses as much as digits as its factorization.

18839969 is an evil number, because the sum of its binary digits is even.

The product of its digits is 839808, while the sum is 53.

The square root of 18839969 is about 4340.5033118292. The cubic root of 18839969 is about 266.0888814855.

The spelling of 18839969 in words is "eighteen million, eight hundred thirty-nine thousand, nine hundred sixty-nine".