12215766751221 has 64 divisors (see below), whose sum is σ = 18432471121920. Its totient is φ = 7128241021440.

The previous prime is 12215766751157. The next prime is 12215766751247.

12215766751221 is nontrivially palindromic in base 10.

12215766751221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 12215766751221 - 2⁶ = 12215766751157 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12215766751921) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 776730660 + ... + 776746386.

It is an arithmetic number, because the mean of its divisors is an integer number (288007361280).

Almost surely, 2^{12215766751221} is an apocalyptic number.

12215766751221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

12215766751221 is a deficient number, since it is larger than the sum of its proper divisors (6216704370699).

12215766751221 is a wasteful number, since it uses less digits than its factorization.

12215766751221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17986.

The product of its digits is 705600, while the sum is 48.

It can be divided in two parts, 1221576 and 6751221, that added together give a palindrome (7972797).

The spelling of 12215766751221 in words is "twelve trillion, two hundred fifteen billion, seven hundred sixty-six million, seven hundred fifty-one thousand, two hundred twenty-one".