12221647 has 4 divisors (see below), whose sum is σ = 12335976. Its totient is φ = 12107320.

The previous prime is 12221611. The next prime is 12221669. The reversal of 12221647 is 74612221.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 74612221 = 19 ⋅3926959.

It is a cyclic number.

It is not a de Polignac number, because 12221647 - 2⁷ = 12221519 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12222647) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 57004 + ... + 57217.

It is an arithmetic number, because the mean of its divisors is an integer number (3083994).

Almost surely, 2^12221647 is an apocalyptic number.

12221647 is a deficient number, since it is larger than the sum of its proper divisors (114329).

12221647 is a wasteful number, since it uses less digits than its factorization.

12221647 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 114328.

The product of its digits is 1344, while the sum is 25.

The square root of 12221647 is about 3495.9472250021. The cubic root of 12221647 is about 230.3438272809.

Adding to 12221647 its reverse (74612221), we get a palindrome (86833868).

The spelling of 12221647 in words is "twelve million, two hundred twenty-one thousand, six hundred forty-seven".