12216157 has 4 divisors (see below), whose sum is σ = 12245596. Its totient is φ = 12186720.

The previous prime is 12216137. The next prime is 12216161. The reversal of 12216157 is 75161221.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 75161221 = 59 ⋅1273919.

It can be written as a sum of positive squares in 2 ways, for example, as 784996 + 11431161 = 886^2 + 3381^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12216157 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 (12216137) 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, 14088 + ... + 14929.

It is an arithmetic number, because the mean of its divisors is an integer number (3061399).

Almost surely, 2^12216157 is an apocalyptic number.

It is an amenable number.

12216157 is a deficient number, since it is larger than the sum of its proper divisors (29439).

12216157 is an equidigital number, since it uses as much as digits as its factorization.

12216157 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29438.

The product of its digits is 840, while the sum is 25.

The square root of 12216157 is about 3495.1619418848. The cubic root of 12216157 is about 230.3093317390.

Adding to 12216157 its reverse (75161221), we get a palindrome (87377378).

The spelling of 12216157 in words is "twelve million, two hundred sixteen thousand, one hundred fifty-seven".