12421220 has 72 divisors (see below), whose sum is σ = 31770816. Its totient is φ = 3995136.

The previous prime is 12421217. The next prime is 12421223. The reversal of 12421220 is 2212421.

It is an interprime number because it is at equal distance from previous prime (12421217) and next prime (12421223).

It is a Harshad number since it is a multiple of its sum of digits (14).

It is a junction number, because it is equal to n+sod(n) for n = 12421195 and 12421204.

It is not an unprimeable number, because it can be changed into a prime (12421223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 40307 + ... + 40613.

Almost surely, 2^12421220 is an apocalyptic number.

12421220 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 12421220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15885408).

12421220 is an abundant number, since it is smaller than the sum of its proper divisors (19349596).

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

12421220 is a wasteful number, since it uses less digits than its factorization.

12421220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 357 (or 338 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 14.

The square root of 12421220 is about 3524.3751219188. The cubic root of 12421220 is about 231.5908613379.

Adding to 12421220 its reverse (2212421), we get a palindrome (14633641).

The spelling of 12421220 in words is "twelve million, four hundred twenty-one thousand, two hundred twenty".