1291320791040 has 832 divisors, whose sum is σ = 5106025635840. Its totient is φ = 272003235840.

The previous prime is 1291320791029. The next prime is 1291320791063. The reversal of 1291320791040 is 401970231921.

It is a self number, because there is not a number n which added to its sum of digits gives 1291320791040.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 302344105 + ... + 302348375.

Almost surely, 2^{1291320791040} is an apocalyptic number.

1291320791040 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 1291320791040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2553012817920).

1291320791040 is an abundant number, since it is smaller than the sum of its proper divisors (3814704844800).

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

1291320791040 is a wasteful number, since it uses less digits than its factorization.

1291320791040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4366 (or 4344 counting only the distinct ones).

The product of its (nonzero) digits is 27216, while the sum is 39.

The spelling of 1291320791040 in words is "one trillion, two hundred ninety-one billion, three hundred twenty million, seven hundred ninety-one thousand, forty".