9891613409121 has 36 divisors (see below), whose sum is σ = 15080803680852. Its totient is φ = 6246777557952.

The previous prime is 9891613409081. The next prime is 9891613409123. The reversal of 9891613409121 is 1219043161989.

It is a happy number.

9891613409121 is a `hidden beast` number, since 9 + 8 + 9 + 1 + 613 + 4 + 0 + 9 + 12 + 1 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 3457781159121 + 6433832250000 = 1859511^2 + 2536500^2 .

It is not a de Polignac number, because 9891613409121 - 2²¹ = 9891611311969 is a prime.

It is not an unprimeable number, because it can be changed into a prime (9891613409123) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 37938615 + ... + 38198451.

It is an arithmetic number, because the mean of its divisors is an integer number (418911213357).

Almost surely, 2^{9891613409121} is an apocalyptic number.

It is an amenable number.

9891613409121 is a deficient number, since it is larger than the sum of its proper divisors (5189190271731).

9891613409121 is a wasteful number, since it uses less digits than its factorization.

9891613409121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 271598 (or 271576 counting only the distinct ones).

The product of its (nonzero) digits is 839808, while the sum is 54.

The spelling of 9891613409121 in words is "nine trillion, eight hundred ninety-one billion, six hundred thirteen million, four hundred nine thousand, one hundred twenty-one".