1323111021 has 4 divisors (see below), whose sum is σ = 1764148032. Its totient is φ = 882074012.

The previous prime is 1323111007. The next prime is 1323111073. The reversal of 1323111021 is 1201113231.

It is a happy number.

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: 1201113231 = 3 ⋅400371077.

It is a cyclic number.

It is not a de Polignac number, because 1323111021 - 2¹¹ = 1323108973 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1323111091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 220518501 + ... + 220518506.

It is an arithmetic number, because the mean of its divisors is an integer number (441037008).

Almost surely, 2^1323111021 is an apocalyptic number.

It is an amenable number.

1323111021 is a deficient number, since it is larger than the sum of its proper divisors (441037011).

1323111021 is an equidigital number, since it uses as much as digits as its factorization.

1323111021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 441037010.

The product of its (nonzero) digits is 36, while the sum is 15.

The square root of 1323111021 is about 36374.5930698888. The cubic root of 1323111021 is about 1097.8224196143.

Adding to 1323111021 its reverse (1201113231), we get a palindrome (2524224252).

The spelling of 1323111021 in words is "one billion, three hundred twenty-three million, one hundred eleven thousand, twenty-one".