18228461 has 2 divisors, whose sum is σ = 18228462. Its totient is φ = 18228460.

The previous prime is 18228439. The next prime is 18228487. The reversal of 18228461 is 16482281.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17598025 + 630436 = 4195^2 + 794^2 .

It is an emirp because it is prime and its reverse (16482281) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18228461 - 2¹⁰ = 18227437 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18228421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9114230 + 9114231.

It is an arithmetic number, because the mean of its divisors is an integer number (9114231).

Almost surely, 2^18228461 is an apocalyptic number.

It is an amenable number.

18228461 is a deficient number, since it is larger than the sum of its proper divisors (1).

18228461 is an equidigital number, since it uses as much as digits as its factorization.

18228461 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6144, while the sum is 32.

The square root of 18228461 is about 4269.4801791319. The cubic root of 18228461 is about 263.1782538628.

The spelling of 18228461 in words is "eighteen million, two hundred twenty-eight thousand, four hundred sixty-one".