18712219 has 4 divisors (see below), whose sum is σ = 18738280. Its totient is φ = 18686160.

The previous prime is 18712201. The next prime is 18712247. The reversal of 18712219 is 91221781.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 18712219 - 2⁷ = 18712091 is a prime.

It is a super-2 number, since 2×18712219² = 700294279807922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18712259) 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, 11922 + ... + 13399.

It is an arithmetic number, because the mean of its divisors is an integer number (4684570).

Almost surely, 2^18712219 is an apocalyptic number.

18712219 is a deficient number, since it is larger than the sum of its proper divisors (26061).

18712219 is an equidigital number, since it uses as much as digits as its factorization.

18712219 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26060.

The product of its digits is 2016, while the sum is 31.

The square root of 18712219 is about 4325.7622449691. The cubic root of 18712219 is about 265.4860854080.

The spelling of 18712219 in words is "eighteen million, seven hundred twelve thousand, two hundred nineteen".