12218523 has 4 divisors (see below), whose sum is σ = 16291368. Its totient is φ = 8145680.

The previous prime is 12218509. The next prime is 12218527. The reversal of 12218523 is 32581221.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 32581221 = 3 ⋅10860407.

It is a cyclic number.

It is not a de Polignac number, because 12218523 - 2⁵ = 12218491 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 12218493 and 12218502.

It is not an unprimeable number, because it can be changed into a prime (12218527) 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 in 3 ways as a sum of consecutive naturals, for example, 2036418 + ... + 2036423.

It is an arithmetic number, because the mean of its divisors is an integer number (4072842).

Almost surely, 2^12218523 is an apocalyptic number.

12218523 is a deficient number, since it is larger than the sum of its proper divisors (4072845).

12218523 is an equidigital number, since it uses as much as digits as its factorization.

12218523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4072844.

The product of its digits is 960, while the sum is 24.

The square root of 12218523 is about 3495.5003933629. The cubic root of 12218523 is about 230.3241993907.

Adding to 12218523 its reverse (32581221), we get a palindrome (44799744).

The spelling of 12218523 in words is "twelve million, two hundred eighteen thousand, five hundred twenty-three".