12217986 has 64 divisors (see below), whose sum is σ = 30159360. Its totient is φ = 3635280.

The previous prime is 12217957. The next prime is 12217987. The reversal of 12217986 is 68971221.

12217986 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 12217986.

It is not an unprimeable number, because it can be changed into a prime (12217987) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 39645 + ... + 39951.

It is an arithmetic number, because the mean of its divisors is an integer number (471240).

Almost surely, 2^12217986 is an apocalyptic number.

12217986 is the 2211-st heptagonal number.

It is a practical number, because each smaller number is the sum of distinct divisors of 12217986, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15079680).

12217986 is an abundant number, since it is smaller than the sum of its proper divisors (17941374).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

12217986 is a wasteful number, since it uses less digits than its factorization.

12217986 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 396 (or 390 counting only the distinct ones).

The product of its digits is 12096, while the sum is 36.

The square root of 12217986 is about 3495.4235794822. The cubic root of 12217986 is about 230.3208251174.

It can be divided in two parts, 122179 and 86, that added together give a triangular number (122265 = T₄₉₄).

The spelling of 12217986 in words is "twelve million, two hundred seventeen thousand, nine hundred eighty-six".