18409201 has 2 divisors, whose sum is σ = 18409202. Its totient is φ = 18409200.

The previous prime is 18409199. The next prime is 18409207. The reversal of 18409201 is 10290481.

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., 17438976 + 970225 = 4176^2 + 985^2 .

It is a cyclic number.

It is not a de Polignac number, because 18409201 - 2¹ = 18409199 is a prime.

Together with 18409199, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (18409207) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9204600 + 9204601.

It is an arithmetic number, because the mean of its divisors is an integer number (9204601).

Almost surely, 2^18409201 is an apocalyptic number.

It is an amenable number.

18409201 is a deficient number, since it is larger than the sum of its proper divisors (1).

18409201 is an equidigital number, since it uses as much as digits as its factorization.

18409201 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 576, while the sum is 25.

The square root of 18409201 is about 4290.5944809548. The cubic root of 18409201 is about 264.0452220129.

Adding to 18409201 its reverse (10290481), we get a palindrome (28699682).

The spelling of 18409201 in words is "eighteen million, four hundred nine thousand, two hundred one".