1291891742208 has 400 divisors, whose sum is σ = 4077590267520. Its totient is φ = 406558310400.

The previous prime is 1291891742203. The next prime is 1291891742231. The reversal of 1291891742208 is 8022471981921.

1291891742208 is a `hidden beast` number, since 1 + 29 + 189 + 17 + 422 + 0 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1291891742203) 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 39 ways as a sum of consecutive naturals, for example, 52698658 + ... + 52723166.

Almost surely, 2^{1291891742208} is an apocalyptic number.

1291891742208 is a gapful number since it is divisible by the number (18) 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 1291891742208, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2038795133760).

1291891742208 is an abundant number, since it is smaller than the sum of its proper divisors (2785698525312).

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

1291891742208 is an equidigital number, since it uses as much as digits as its factorization.

1291891742208 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24611 (or 24586 counting only the distinct ones).

The product of its (nonzero) digits is 1161216, while the sum is 54.

The spelling of 1291891742208 in words is "one trillion, two hundred ninety-one billion, eight hundred ninety-one million, seven hundred forty-two thousand, two hundred eight".