18543643 has 2 divisors, whose sum is σ = 18543644. Its totient is φ = 18543642.

The previous prime is 18543619. The next prime is 18543649. The reversal of 18543643 is 34634581.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18543643 is a prime.

It is a super-2 number, since 2×18543643² = 687733391422898, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 18543599 and 18543608.

It is not a weakly prime, because it can be changed into another prime (18543649) 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, 9271821 + 9271822.

It is an arithmetic number, because the mean of its divisors is an integer number (9271822).

Almost surely, 2^18543643 is an apocalyptic number.

18543643 is a deficient number, since it is larger than the sum of its proper divisors (1).

18543643 is an equidigital number, since it uses as much as digits as its factorization.

18543643 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 34560, while the sum is 34.

The square root of 18543643 is about 4306.2330406052. The cubic root of 18543643 is about 264.6864358108.

The spelling of 18543643 in words is "eighteen million, five hundred forty-three thousand, six hundred forty-three".