1321012443 has 24 divisors (see below), whose sum is σ = 1818609408. Its totient is φ = 852916896.

The previous prime is 1321012403. The next prime is 1321012457. The reversal of 1321012443 is 3442101231.

It is not a de Polignac number, because 1321012443 - 2¹² = 1321008347 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1321012403) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1079530 + ... + 1080752.

It is an arithmetic number, because the mean of its divisors is an integer number (75775392).

Almost surely, 2^1321012443 is an apocalyptic number.

1321012443 is a deficient number, since it is larger than the sum of its proper divisors (497596965).

1321012443 is a wasteful number, since it uses less digits than its factorization.

1321012443 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1563 (or 1526 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 21.

The square root of 1321012443 is about 36345.7348666938. The cubic root of 1321012443 is about 1097.2416960860.

Adding to 1321012443 its reverse (3442101231), we get a palindrome (4763113674).

The spelling of 1321012443 in words is "one billion, three hundred twenty-one million, twelve thousand, four hundred forty-three".