18318401 has 16 divisors (see below), whose sum is σ = 20379600. Its totient is φ = 16386048.

The previous prime is 18318389. The next prime is 18318437. The reversal of 18318401 is 10481381.

It is a Cunningham number, because it is equal to 4280²+1.

It can be written as a sum of positive squares in 8 ways, for example, as 2310400 + 16008001 = 1520^2 + 4001^2 .

It is a cyclic number.

It is not a de Polignac number, because 18318401 - 2¹⁴ = 18302017 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18318101) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 35735 + ... + 36243.

It is an arithmetic number, because the mean of its divisors is an integer number (1273725).

Almost surely, 2^18318401 is an apocalyptic number.

It is an amenable number.

18318401 is a deficient number, since it is larger than the sum of its proper divisors (2061199).

18318401 is a wasteful number, since it uses less digits than its factorization.

18318401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 628.

The product of its (nonzero) digits is 768, while the sum is 26.

The square root of 18318401 is about 4280.0001168224. Note that the first 3 decimals coincide. The cubic root of 18318401 is about 263.6103881409.

Adding to 18318401 its reverse (10481381), we get a palindrome (28799782).

The spelling of 18318401 in words is "eighteen million, three hundred eighteen thousand, four hundred one".