8961191391 has 8 divisors (see below), whose sum is σ = 12467744640. Its totient is φ = 5714382872.

The previous prime is 8961191377. The next prime is 8961191401. The reversal of 8961191391 is 1931911698.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 8961191391 - 2¹¹ = 8961189343 is a prime.

It is a super-2 number, since 2×8961191391² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 8961191391.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8961199391) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 64936101 + ... + 64936238.

It is an arithmetic number, because the mean of its divisors is an integer number (1558468080).

Almost surely, 2^8961191391 is an apocalyptic number.

8961191391 is a deficient number, since it is larger than the sum of its proper divisors (3506553249).

8961191391 is a wasteful number, since it uses less digits than its factorization.

8961191391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129872365.

The product of its digits is 104976, while the sum is 48.

The square root of 8961191391 is about 94663.5695027395. The cubic root of 8961191391 is about 2077.0896945584.

The spelling of 8961191391 in words is "eight billion, nine hundred sixty-one million, one hundred ninety-one thousand, three hundred ninety-one".