1312355440 has 80 divisors (see below), whose sum is σ = 3341500416. Its totient is φ = 475372800.

The previous prime is 1312355423. The next prime is 1312355489. The reversal of 1312355440 is 445532131.

It is a tau number, because it is divible by the number of its divisors (80).

It is a junction number, because it is equal to n+sod(n) for n = 1312355399 and 1312355408.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 235729 + ... + 241231.

Almost surely, 2^1312355440 is an apocalyptic number.

1312355440 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 1312355440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1670750208).

1312355440 is an abundant number, since it is smaller than the sum of its proper divisors (2029144976).

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

1312355440 is a wasteful number, since it uses less digits than its factorization.

1312355440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5798 (or 5792 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 28.

The square root of 1312355440 is about 36226.4466929894. The cubic root of 1312355440 is about 1094.8395864620.

Adding to 1312355440 its reverse (445532131), we get a palindrome (1757887571).

The spelling of 1312355440 in words is "one billion, three hundred twelve million, three hundred fifty-five thousand, four hundred forty".