12215322857 has 4 divisors (see below), whose sum is σ = 12545466756. Its totient is φ = 11885178960.

The previous prime is 12215322829. The next prime is 12215322877. The reversal of 12215322857 is 75822351221.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 75822351221 = 1669 ⋅45429809.

It can be written as a sum of positive squares in 2 ways, for example, as 10012804096 + 2202518761 = 100064^2 + 46931^2 .

It is a cyclic number.

It is not a de Polignac number, because 12215322857 - 2⁸ = 12215322601 is a prime.

It is a super-2 number, since 2×12215322857² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 12215322857.

It is not an unprimeable number, because it can be changed into a prime (12215322827) 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, 165071894 + ... + 165071967.

It is an arithmetic number, because the mean of its divisors is an integer number (3136366689).

Almost surely, 2^12215322857 is an apocalyptic number.

It is an amenable number.

12215322857 is a deficient number, since it is larger than the sum of its proper divisors (330143899).

12215322857 is an equidigital number, since it uses as much as digits as its factorization.

12215322857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 330143898.

The product of its digits is 67200, while the sum is 38.

The spelling of 12215322857 in words is "twelve billion, two hundred fifteen million, three hundred twenty-two thousand, eight hundred fifty-seven".