18000401 has 2 divisors, whose sum is σ = 18000402. Its totient is φ = 18000400.

The previous prime is 18000397. The next prime is 18000403. The reversal of 18000401 is 10400081.

It is a happy number.

18000401 is nontrivially palindromic in base 4.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17977600 + 22801 = 4240^2 + 151^2 .

It is a cyclic number.

It is not a de Polignac number, because 18000401 - 2² = 18000397 is a prime.

Together with 18000403, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (18000403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9000200 + 9000201.

It is an arithmetic number, because the mean of its divisors is an integer number (9000201).

Almost surely, 2^18000401 is an apocalyptic number.

It is an amenable number.

18000401 is a deficient number, since it is larger than the sum of its proper divisors (1).

18000401 is an equidigital number, since it uses as much as digits as its factorization.

18000401 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32, while the sum is 14.

The square root of 18000401 is about 4242.6879451593. The cubic root of 18000401 is about 262.0760855496.

Adding to 18000401 its reverse (10400081), we get a palindrome (28400482).

The spelling of 18000401 in words is "eighteen million, four hundred one", and thus it is an aban number.