12665220 has 48 divisors (see below), whose sum is σ = 36294720. Its totient is φ = 3298176.

The previous prime is 12665207. The next prime is 12665243. The reversal of 12665220 is 2256621.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 126 + ... + 5034.

It is an arithmetic number, because the mean of its divisors is an integer number (756140).

Almost surely, 2^12665220 is an apocalyptic number.

12665220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 12665220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18147360).

12665220 is an abundant number, since it is smaller than the sum of its proper divisors (23629500).

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

12665220 is a wasteful number, since it uses less digits than its factorization.

12665220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4964 (or 4962 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 24.

The square root of 12665220 is about 3558.8228390860. The cubic root of 12665220 is about 233.0974805017.

The spelling of 12665220 in words is "twelve million, six hundred sixty-five thousand, two hundred twenty".