12221157 has 16 divisors (see below), whose sum is σ = 17978688. Its totient is φ = 7336320.

The previous prime is 12221117. The next prime is 12221171. The reversal of 12221157 is 75112221.

It is not a de Polignac number, because 12221157 - 2⁷ = 12221029 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12221107) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2223 + ... + 5420.

It is an arithmetic number, because the mean of its divisors is an integer number (1123668).

Almost surely, 2^12221157 is an apocalyptic number.

It is an amenable number.

12221157 is a deficient number, since it is larger than the sum of its proper divisors (5757531).

12221157 is a wasteful number, since it uses less digits than its factorization.

12221157 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7700.

The product of its digits is 280, while the sum is 21.

The square root of 12221157 is about 3495.8771431502. The cubic root of 12221157 is about 230.3407488638.

Adding to 12221157 its reverse (75112221), we get a palindrome (87333378).

The spelling of 12221157 in words is "twelve million, two hundred twenty-one thousand, one hundred fifty-seven".