18186461 has 2 divisors, whose sum is σ = 18186462. Its totient is φ = 18186460.

The previous prime is 18186457. The next prime is 18186503. The reversal of 18186461 is 16468181.

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., 12924025 + 5262436 = 3595^2 + 2294^2 .

It is a cyclic number.

It is not a de Polignac number, because 18186461 - 2² = 18186457 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18186431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9093230 + 9093231.

It is an arithmetic number, because the mean of its divisors is an integer number (9093231).

Almost surely, 2^18186461 is an apocalyptic number.

It is an amenable number.

18186461 is a deficient number, since it is larger than the sum of its proper divisors (1).

18186461 is an equidigital number, since it uses as much as digits as its factorization.

18186461 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9216, while the sum is 35.

The square root of 18186461 is about 4264.5587110509. The cubic root of 18186461 is about 262.9759696993.

The spelling of 18186461 in words is "eighteen million, one hundred eighty-six thousand, four hundred sixty-one".