12216415 has 4 divisors (see below), whose sum is σ = 14659704. Its totient is φ = 9773128.

The previous prime is 12216403. The next prime is 12216419. The reversal of 12216415 is 51461221.

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 12216415 - 2¹⁷ = 12085343 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 (12216419) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1221637 + ... + 1221646.

It is an arithmetic number, because the mean of its divisors is an integer number (3664926).

Almost surely, 2^12216415 is an apocalyptic number.

12216415 is a deficient number, since it is larger than the sum of its proper divisors (2443289).

12216415 is an equidigital number, since it uses as much as digits as its factorization.

12216415 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2443288.

The product of its digits is 480, while the sum is 22.

The square root of 12216415 is about 3495.1988498510. The cubic root of 12216415 is about 230.3109530724.

Adding to 12216415 its reverse (51461221), we get a palindrome (63677636).

The spelling of 12216415 in words is "twelve million, two hundred sixteen thousand, four hundred fifteen".