1312666440 has 96 divisors (see below), whose sum is σ = 4078788480. Its totient is φ = 337947904.

The previous prime is 1312666417. The next prime is 1312666489. The reversal of 1312666440 is 446662131.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 94417 + ... + 107423.

It is an arithmetic number, because the mean of its divisors is an integer number (42487380).

Almost surely, 2^1312666440 is an apocalyptic number.

1312666440 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 1312666440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2039394240).

1312666440 is an abundant number, since it is smaller than the sum of its proper divisors (2766122040).

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

1312666440 is a wasteful number, since it uses less digits than its factorization.

1312666440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13079 (or 13046 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 33.

The square root of 1312666440 is about 36230.7388828878. The cubic root of 1312666440 is about 1094.9260641057.

The spelling of 1312666440 in words is "one billion, three hundred twelve million, six hundred sixty-six thousand, four hundred forty".