12451221 has 12 divisors (see below), whose sum is σ = 18023148. Its totient is φ = 8283264.

The previous prime is 12451217. The next prime is 12451223. The reversal of 12451221 is 12215421.

It can be written as a sum of positive squares in 2 ways, for example, as 5948721 + 6502500 = 2439^2 + 2550^2 .

It is not a de Polignac number, because 12451221 - 2² = 12451217 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 12451194 and 12451203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12451223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4171 + ... + 6503.

It is an arithmetic number, because the mean of its divisors is an integer number (1501929).

Almost surely, 2^12451221 is an apocalyptic number.

It is an amenable number.

12451221 is a deficient number, since it is larger than the sum of its proper divisors (5571927).

12451221 is a wasteful number, since it uses less digits than its factorization.

12451221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2932 (or 2929 counting only the distinct ones).

The product of its digits is 160, while the sum is 18.

The square root of 12451221 is about 3528.6287705000. The cubic root of 12451221 is about 231.7771653971. Note that the first 3 decimals are identical.

Adding to 12451221 its reverse (12215421), we get a palindrome (24666642).

The spelling of 12451221 in words is "twelve million, four hundred fifty-one thousand, two hundred twenty-one".