18146509 has 2 divisors, whose sum is σ = 18146510. Its totient is φ = 18146508.

The previous prime is 18146507. The next prime is 18146519. The reversal of 18146509 is 90564181.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16990884 + 1155625 = 4122^2 + 1075^2 .

It is an emirp because it is prime and its reverse (90564181) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18146509 - 2¹ = 18146507 is a prime.

Together with 18146507, 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 (18146507) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9073254 + 9073255.

It is an arithmetic number, because the mean of its divisors is an integer number (9073255).

Almost surely, 2^18146509 is an apocalyptic number.

It is an amenable number.

18146509 is a deficient number, since it is larger than the sum of its proper divisors (1).

18146509 is an equidigital number, since it uses as much as digits as its factorization.

18146509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8640, while the sum is 34.

The square root of 18146509 is about 4259.8719464322. The cubic root of 18146509 is about 262.7832600633.

The spelling of 18146509 in words is "eighteen million, one hundred forty-six thousand, five hundred nine".