18227917 has 4 divisors (see below), whose sum is σ = 18389340. Its totient is φ = 18066496.

The previous prime is 18227887. The next prime is 18227933. The reversal of 18227917 is 71972281.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 71972281 = 6863 ⋅10487.

It can be written as a sum of positive squares in 2 ways, for example, as 2019241 + 16208676 = 1421^2 + 4026^2 .

It is a cyclic number.

It is not a de Polignac number, because 18227917 - 2¹¹ = 18225869 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18227947) 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 in 3 ways as a sum of consecutive naturals, for example, 80542 + ... + 80767.

It is an arithmetic number, because the mean of its divisors is an integer number (4597335).

Almost surely, 2^18227917 is an apocalyptic number.

It is an amenable number.

18227917 is a deficient number, since it is larger than the sum of its proper divisors (161423).

18227917 is a wasteful number, since it uses less digits than its factorization.

18227917 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 161422.

The product of its digits is 14112, while the sum is 37.

The square root of 18227917 is about 4269.4164706667. The cubic root of 18227917 is about 263.1756357885.

The spelling of 18227917 in words is "eighteen million, two hundred twenty-seven thousand, nine hundred seventeen".