12221257 has 4 divisors (see below), whose sum is σ = 12752640. Its totient is φ = 11689876.

The previous prime is 12221243. The next prime is 12221263. The reversal of 12221257 is 75212221.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12221257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12221207) 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, 265657 + ... + 265702.

It is an arithmetic number, because the mean of its divisors is an integer number (3188160).

Almost surely, 2^12221257 is an apocalyptic number.

It is an amenable number.

12221257 is a deficient number, since it is larger than the sum of its proper divisors (531383).

12221257 is an equidigital number, since it uses as much as digits as its factorization.

12221257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 531382.

The product of its digits is 560, while the sum is 22.

The square root of 12221257 is about 3495.8914456831. The cubic root of 12221257 is about 230.3413771189.

Adding to 12221257 its reverse (75212221), we get a palindrome (87433478).

The spelling of 12221257 in words is "twelve million, two hundred twenty-one thousand, two hundred fifty-seven".