18146521 has 2 divisors, whose sum is σ = 18146522. Its totient is φ = 18146520.

The previous prime is 18146519. The next prime is 18146549. The reversal of 18146521 is 12564181.

It is an a-pointer prime, because the next prime (18146549) can be obtained adding 18146521 to its sum of digits (28).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17977600 + 168921 = 4240^2 + 411^2 .

It is a cyclic number.

It is not a de Polignac number, because 18146521 - 2¹ = 18146519 is a prime.

Together with 18146519, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18146521.

It is not a weakly prime, because it can be changed into another prime (18146551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9073260 + 9073261.

It is an arithmetic number, because the mean of its divisors is an integer number (9073261).

Almost surely, 2^18146521 is an apocalyptic number.

It is an amenable number.

18146521 is a deficient number, since it is larger than the sum of its proper divisors (1).

18146521 is an equidigital number, since it uses as much as digits as its factorization.

18146521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1920, while the sum is 28.

The square root of 18146521 is about 4259.8733549250. The cubic root of 18146521 is about 262.7833179881.

The spelling of 18146521 in words is "eighteen million, one hundred forty-six thousand, five hundred twenty-one".