1291161319940 has 24 divisors (see below), whose sum is σ = 2711873072832. Its totient is φ = 516381804000.

The previous prime is 1291161319933. The next prime is 1291161319949. The reversal of 1291161319940 is 499131611921.

It is a happy number.

It is a Smith number, since the sum of its digits (47) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (1291161319949) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5042186 + ... + 5292065.

It is an arithmetic number, because the mean of its divisors is an integer number (112994711368).

Almost surely, 2^{1291161319940} is an apocalyptic number.

1291161319940 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1291161319940 is an abundant number, since it is smaller than the sum of its proper divisors (1420711752892).

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

1291161319940 is a wasteful number, since it uses less digits than its factorization.

1291161319940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10340507 (or 10340505 counting only the distinct ones).

The product of its (nonzero) digits is 104976, while the sum is 47.

The spelling of 1291161319940 in words is "one trillion, two hundred ninety-one billion, one hundred sixty-one million, three hundred nineteen thousand, nine hundred forty".