9891960691989 has 4 divisors (see below), whose sum is σ = 13189280922656. Its totient is φ = 6594640461324.

The previous prime is 9891960691981. The next prime is 9891960691999.

9891960691989 is nontrivially palindromic in base 10.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 9891960691989 - 2³ = 9891960691981 is a prime.

It is a super-2 number, since 2×9891960691989² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9891960691981) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1648660115329 + ... + 1648660115334.

It is an arithmetic number, because the mean of its divisors is an integer number (3297320230664).

Almost surely, 2^{9891960691989} is an apocalyptic number.

It is an amenable number.

9891960691989 is a deficient number, since it is larger than the sum of its proper divisors (3297320230667).

9891960691989 is a wasteful number, since it uses less digits than its factorization.

9891960691989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3297320230666.

The product of its (nonzero) digits is 1224440064, while the sum is 84.

The spelling of 9891960691989 in words is "nine trillion, eight hundred ninety-one billion, nine hundred sixty million, six hundred ninety-one thousand, nine hundred eighty-nine".