1221303323443 has 16 divisors (see below), whose sum is σ = 1398050357440. Its totient is φ = 1045126250496.

The previous prime is 1221303323441. The next prime is 1221303323467. The reversal of 1221303323443 is 3443233031221.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 1221303323443 - 2¹ = 1221303323441 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221303323441) 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, 12776755 + ... + 12871987.

It is an arithmetic number, because the mean of its divisors is an integer number (87378147340).

Almost surely, 2^{1221303323443} is an apocalyptic number.

1221303323443 is a deficient number, since it is larger than the sum of its proper divisors (176747033997).

1221303323443 is an equidigital number, since it uses as much as digits as its factorization.

1221303323443 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98206.

The product of its (nonzero) digits is 31104, while the sum is 31.

Adding to 1221303323443 its reverse (3443233031221), we get a palindrome (4664536354664).

The spelling of 1221303323443 in words is "one trillion, two hundred twenty-one billion, three hundred three million, three hundred twenty-three thousand, four hundred forty-three".