18240511 has 2 divisors, whose sum is σ = 18240512. Its totient is φ = 18240510.

The previous prime is 18240479. The next prime is 18240517. The reversal of 18240511 is 11504281.

It is a strong prime.

It is an emirp because it is prime and its reverse (11504281) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18240511 - 2⁵ = 18240479 is a prime.

It is a super-2 number, since 2×18240511² = 665432483082242, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18240517) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9120255 + 9120256.

It is an arithmetic number, because the mean of its divisors is an integer number (9120256).

Almost surely, 2^18240511 is an apocalyptic number.

18240511 is a deficient number, since it is larger than the sum of its proper divisors (1).

18240511 is an equidigital number, since it uses as much as digits as its factorization.

18240511 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 320, while the sum is 22.

The square root of 18240511 is about 4270.8911248122. The cubic root of 18240511 is about 263.2362327822.

Adding to 18240511 its reverse (11504281), we get a palindrome (29744792).

The spelling of 18240511 in words is "eighteen million, two hundred forty thousand, five hundred eleven".