12215660 has 12 divisors (see below), whose sum is σ = 25652928. Its totient is φ = 4886256.

The previous prime is 12215657. The next prime is 12215681. The reversal of 12215660 is 6651221.

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 3 ways as a sum of consecutive naturals, for example, 305372 + ... + 305411.

It is an arithmetic number, because the mean of its divisors is an integer number (2137744).

Almost surely, 2^12215660 is an apocalyptic number.

12215660 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

12215660 is an abundant number, since it is smaller than the sum of its proper divisors (13437268).

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

12215660 is a wasteful number, since it uses less digits than its factorization.

12215660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 610792 (or 610790 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 12215660 is about 3495.0908428823. The cubic root of 12215660 is about 230.3062084084.

Adding to 12215660 its reverse (6651221), we get a palindrome (18866881).

The spelling of 12215660 in words is "twelve million, two hundred fifteen thousand, six hundred sixty".