12721447 has 2 divisors, whose sum is σ = 12721448. Its totient is φ = 12721446.

The previous prime is 12721441. The next prime is 12721477. The reversal of 12721447 is 74412721.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 12721447 - 2¹⁵ = 12688679 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12721441) 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 as a sum of consecutive naturals, namely, 6360723 + 6360724.

It is an arithmetic number, because the mean of its divisors is an integer number (6360724).

Almost surely, 2^12721447 is an apocalyptic number.

12721447 is a deficient number, since it is larger than the sum of its proper divisors (1).

12721447 is an equidigital number, since it uses as much as digits as its factorization.

12721447 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3136, while the sum is 28.

The square root of 12721447 is about 3566.7137535833. The cubic root of 12721447 is about 233.4419152231.

The spelling of 12721447 in words is "twelve million, seven hundred twenty-one thousand, four hundred forty-seven".