18718523 has 2 divisors, whose sum is σ = 18718524. Its totient is φ = 18718522.

The previous prime is 18718519. The next prime is 18718541. The reversal of 18718523 is 32581781.

It is a weak prime.

It is an emirp because it is prime and its reverse (32581781) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18718523 - 2² = 18718519 is a prime.

It is not a weakly prime, because it can be changed into another prime (18718123) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9359261 + 9359262.

It is an arithmetic number, because the mean of its divisors is an integer number (9359262).

Almost surely, 2^18718523 is an apocalyptic number.

18718523 is a deficient number, since it is larger than the sum of its proper divisors (1).

18718523 is an equidigital number, since it uses as much as digits as its factorization.

18718523 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13440, while the sum is 35.

The square root of 18718523 is about 4326.4908413170. The cubic root of 18718523 is about 265.5158954548.

The spelling of 18718523 in words is "eighteen million, seven hundred eighteen thousand, five hundred twenty-three".