1312440320 has 120 divisors (see below), whose sum is σ = 3242360184. Its totient is φ = 509607936.

The previous prime is 1312440319. The next prime is 1312440323. The reversal of 1312440320 is 230442131.

It can be written as a sum of positive squares in 4 ways, for example, as 135675904 + 1176764416 = 11648^2 + 34304^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 1312440292 and 1312440301.

It is not an unprimeable number, because it can be changed into a prime (1312440323) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3030824 + ... + 3031256.

Almost surely, 2^1312440320 is an apocalyptic number.

1312440320 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 1312440320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1621180092).

1312440320 is an abundant number, since it is smaller than the sum of its proper divisors (1929919864).

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

1312440320 is an frugal number, since it uses more digits than its factorization.

1312440320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 503 (or 477 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 20.

The square root of 1312440320 is about 36227.6181938587. The cubic root of 1312440320 is about 1094.8631898187.

Adding to 1312440320 its reverse (230442131), we get a palindrome (1542882451).

The spelling of 1312440320 in words is "one billion, three hundred twelve million, four hundred forty thousand, three hundred twenty".