12821247 has 20 divisors (see below), whose sum is σ = 20281536. Its totient is φ = 8043840.

The previous prime is 12821227. The next prime is 12821261. The reversal of 12821247 is 74212821.

It is not a de Polignac number, because 12821247 - 2⁷ = 12821119 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a self number, because there is not a number n which added to its sum of digits gives 12821247.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12821227) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 3279 + ... + 6032.

Almost surely, 2^12821247 is an apocalyptic number.

12821247 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

12821247 is a deficient number, since it is larger than the sum of its proper divisors (7460289).

12821247 is an equidigital number, since it uses as much as digits as its factorization.

12821247 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9340 (or 9331 counting only the distinct ones).

The product of its digits is 1792, while the sum is 27.

The square root of 12821247 is about 3580.6768913154. The cubic root of 12821247 is about 234.0507779350.

The spelling of 12821247 in words is "twelve million, eight hundred twenty-one thousand, two hundred forty-seven".