1321440443 has 4 divisors (see below), whose sum is σ = 1390989960. Its totient is φ = 1251890928.

The previous prime is 1321440437. The next prime is 1321440451. The reversal of 1321440443 is 3440441231.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1321440443 - 2²⁸ = 1053004987 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1321443443) 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, 34774730 + ... + 34774767.

It is an arithmetic number, because the mean of its divisors is an integer number (347747490).

Almost surely, 2^1321440443 is an apocalyptic number.

1321440443 is a deficient number, since it is larger than the sum of its proper divisors (69549517).

1321440443 is an equidigital number, since it uses as much as digits as its factorization.

1321440443 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69549516.

The product of its (nonzero) digits is 4608, while the sum is 26.

The square root of 1321440443 is about 36351.6222884206. The cubic root of 1321440443 is about 1097.3601831701.

Adding to 1321440443 its reverse (3440441231), we get a palindrome (4761881674).

The spelling of 1321440443 in words is "one billion, three hundred twenty-one million, four hundred forty thousand, four hundred forty-three".