18243564551 has 2 divisors, whose sum is σ = 18243564552. Its totient is φ = 18243564550.

The previous prime is 18243564529. The next prime is 18243564553. The reversal of 18243564551 is 15546534281.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18243564551 is a prime.

Together with 18243564553, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18243564553) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9121782275 + 9121782276.

It is an arithmetic number, because the mean of its divisors is an integer number (9121782276).

Almost surely, 2^18243564551 is an apocalyptic number.

18243564551 is a deficient number, since it is larger than the sum of its proper divisors (1).

18243564551 is an equidigital number, since it uses as much as digits as its factorization.

18243564551 is an evil number, because the sum of its binary digits is even.

The product of its digits is 576000, while the sum is 44.

The spelling of 18243564551 in words is "eighteen billion, two hundred forty-three million, five hundred sixty-four thousand, five hundred fifty-one".