18318541 has 2 divisors, whose sum is σ = 18318542. Its totient is φ = 18318540.

The previous prime is 18318539. The next prime is 18318569. The reversal of 18318541 is 14581381.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17724100 + 594441 = 4210^2 + 771^2 .

It is an emirp because it is prime and its reverse (14581381) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18318541 - 2¹ = 18318539 is a prime.

Together with 18318539, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18318341) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9159270 + 9159271.

It is an arithmetic number, because the mean of its divisors is an integer number (9159271).

Almost surely, 2^18318541 is an apocalyptic number.

It is an amenable number.

18318541 is a deficient number, since it is larger than the sum of its proper divisors (1).

18318541 is an equidigital number, since it uses as much as digits as its factorization.

18318541 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3840, while the sum is 31.

The square root of 18318541 is about 4280.0164719309. The cubic root of 18318541 is about 263.6110596944.

Adding to 18318541 its product of digits (3840), we get a palindrome (18322381).

The spelling of 18318541 in words is "eighteen million, three hundred eighteen thousand, five hundred forty-one".