12215110421 has 4 divisors (see below), whose sum is σ = 12296005344. Its totient is φ = 12134215500.

The previous prime is 12215110417. The next prime is 12215110423. The reversal of 12215110421 is 12401151221.

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, and also an emirpimes, since its reverse is a distinct semiprime: 12401151221 = 61 ⋅203297561.

It is a cyclic number.

It is not a de Polignac number, because 12215110421 - 2² = 12215110417 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12215110393 and 12215110402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12215110423) 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, 40447235 + ... + 40447536.

It is an arithmetic number, because the mean of its divisors is an integer number (3074001336).

Almost surely, 2^12215110421 is an apocalyptic number.

It is an amenable number.

12215110421 is a deficient number, since it is larger than the sum of its proper divisors (80894923).

12215110421 is an equidigital number, since it uses as much as digits as its factorization.

12215110421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80894922.

The product of its (nonzero) digits is 160, while the sum is 20.

Adding to 12215110421 its reverse (12401151221), we get a palindrome (24616261642).

The spelling of 12215110421 in words is "twelve billion, two hundred fifteen million, one hundred ten thousand, four hundred twenty-one".