1312323440 has 40 divisors (see below), whose sum is σ = 3054887808. Its totient is φ = 524286720.

The previous prime is 1312323433. The next prime is 1312323451. The reversal of 1312323440 is 443232131.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×1312323440² = 3444385622346867200, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 58625 + ... + 77855.

Almost surely, 2^1312323440 is an apocalyptic number.

1312323440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1312323440 is an abundant number, since it is smaller than the sum of its proper divisors (1742564368).

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

1312323440 is a wasteful number, since it uses less digits than its factorization.

1312323440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20097 (or 20091 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 23.

The square root of 1312323440 is about 36226.0050240156. The cubic root of 1312323440 is about 1094.8306876656.

Adding to 1312323440 its reverse (443232131), we get a palindrome (1755555571).

It can be divided in two parts, 13123 and 23440, that added together give a palindrome (36563).

The spelling of 1312323440 in words is "one billion, three hundred twelve million, three hundred twenty-three thousand, four hundred forty".