1991071272960 has 1664 divisors, whose sum is σ = 8931770449920. Its totient is φ = 408748032000.

The previous prime is 1991071272943. The next prime is 1991071273039. The reversal of 1991071272960 is 692721701991.

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

It is a junction number, because it is equal to n+sod(n) for n = 1991071272897 and 1991071272906.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 4300369689 + ... + 4300370151.

Almost surely, 2^{1991071272960} is an apocalyptic number.

1991071272960 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 1991071272960, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4465885224960).

1991071272960 is an abundant number, since it is smaller than the sum of its proper divisors (6940699176960).

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

1991071272960 is a wasteful number, since it uses less digits than its factorization.

1991071272960 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 620 (or 592 counting only the distinct ones).

The product of its (nonzero) digits is 857304, while the sum is 54.

The spelling of 1991071272960 in words is "one trillion, nine hundred ninety-one billion, seventy-one million, two hundred seventy-two thousand, nine hundred sixty".