1323320440 has 64 divisors (see below), whose sum is σ = 3260930400. Its totient is φ = 480317952.

The previous prime is 1323320437. The next prime is 1323320447. The reversal of 1323320440 is 440233231.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1323320447) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9114 + ... + 52246.

Almost surely, 2^1323320440 is an apocalyptic number.

1323320440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1323320440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1630465200).

1323320440 is an abundant number, since it is smaller than the sum of its proper divisors (1937609960).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1323320440 is a wasteful number, since it uses less digits than its factorization.

1323320440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43216 (or 43212 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 22.

The square root of 1323320440 is about 36377.4715998790. The cubic root of 1323320440 is about 1097.8803368364.

Adding to 1323320440 its reverse (440233231), we get a palindrome (1763553671).

The spelling of 1323320440 in words is "one billion, three hundred twenty-three million, three hundred twenty thousand, four hundred forty".