1312321340 has 96 divisors (see below), whose sum is σ = 3169575360. Its totient is φ = 451942400.

The previous prime is 1312321337. The next prime is 1312321391. The reversal of 1312321340 is 431232131.

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

It is a congruent number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 336200 + ... + 340080.

It is an arithmetic number, because the mean of its divisors is an integer number (33016410).

Almost surely, 2^1312321340 is an apocalyptic number.

1312321340 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 1312321340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1584787680).

1312321340 is an abundant number, since it is smaller than the sum of its proper divisors (1857254020).

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

1312321340 is a wasteful number, since it uses less digits than its factorization.

1312321340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3983 (or 3981 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 20.

The square root of 1312321340 is about 36225.9760393009. The cubic root of 1312321340 is about 1094.8301036771.

Adding to 1312321340 its reverse (431232131), we get a palindrome (1743553471).

The spelling of 1312321340 in words is "one billion, three hundred twelve million, three hundred twenty-one thousand, three hundred forty".