18443969 has 2 divisors, whose sum is σ = 18443970. Its totient is φ = 18443968.

The previous prime is 18443951. The next prime is 18443987. The reversal of 18443969 is 96934481.

It is a balanced prime because it is at equal distance from previous prime (18443951) and next prime (18443987).

It can be written as a sum of positive squares in only one way, i.e., 11992369 + 6451600 = 3463^2 + 2540^2 .

It is a cyclic number.

It is not a de Polignac number, because 18443969 - 2⁸ = 18443713 is a prime.

It is a super-2 number, since 2×18443969² = 680359984945922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (18443569) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9221984 + 9221985.

It is an arithmetic number, because the mean of its divisors is an integer number (9221985).

Almost surely, 2^18443969 is an apocalyptic number.

It is an amenable number.

18443969 is a deficient number, since it is larger than the sum of its proper divisors (1).

18443969 is an equidigital number, since it uses as much as digits as its factorization.

18443969 is an evil number, because the sum of its binary digits is even.

The product of its digits is 186624, while the sum is 44.

The square root of 18443969 is about 4294.6442227500. The cubic root of 18443969 is about 264.2113445758.

The spelling of 18443969 in words is "eighteen million, four hundred forty-three thousand, nine hundred sixty-nine".