12216505 has 8 divisors (see below), whose sum is σ = 16754112. Its totient is φ = 8377008.

The previous prime is 12216499. The next prime is 12216539. The reversal of 12216505 is 50561221.

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 12216505 - 2³ = 12216497 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 174487 + ... + 174556.

It is an arithmetic number, because the mean of its divisors is an integer number (2094264).

Almost surely, 2^12216505 is an apocalyptic number.

It is an amenable number.

12216505 is a deficient number, since it is larger than the sum of its proper divisors (4537607).

12216505 is an equidigital number, since it uses as much as digits as its factorization.

12216505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 349055.

The product of its (nonzero) digits is 600, while the sum is 22.

The square root of 12216505 is about 3495.2117246313. The cubic root of 12216505 is about 230.3115186484.

Adding to 12216505 its reverse (50561221), we get a palindrome (62777726).

It can be divided in two parts, 12216 and 505, that added together give a palindrome (12721).

The spelling of 12216505 in words is "twelve million, two hundred sixteen thousand, five hundred five".