12181819 has 8 divisors (see below), whose sum is σ = 13154400. Its totient is φ = 11214336.

The previous prime is 12181817. The next prime is 12181823. The reversal of 12181819 is 91818121.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 12181819 - 2¹ = 12181817 is a prime.

It is a super-2 number, since 2×12181819² = 296793428297522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12181817) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4794 + ... + 6880.

It is an arithmetic number, because the mean of its divisors is an integer number (1644300).

Almost surely, 2^12181819 is an apocalyptic number.

12181819 is a deficient number, since it is larger than the sum of its proper divisors (972581).

12181819 is a wasteful number, since it uses less digits than its factorization.

12181819 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2549.

The product of its digits is 1152, while the sum is 31.

The square root of 12181819 is about 3490.2462663829. The cubic root of 12181819 is about 230.0933395571.

It can be divided in two parts, 121 and 81819, that multiplied together give a palindrome (9900099).

The spelling of 12181819 in words is "twelve million, one hundred eighty-one thousand, eight hundred nineteen".