9991154791 has 16 divisors (see below), whose sum is σ = 10614051360. Its totient is φ = 9388431360.

The previous prime is 9991154783. The next prime is 9991154819. The reversal of 9991154791 is 1974511999.

9991154791 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 9991154791 - 2³ = 9991154783 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9991151791) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 336151 + ... + 364663.

It is an arithmetic number, because the mean of its divisors is an integer number (663378210).

Almost surely, 2^9991154791 is an apocalyptic number.

9991154791 is a deficient number, since it is larger than the sum of its proper divisors (622896569).

9991154791 is a wasteful number, since it uses less digits than its factorization.

9991154791 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28866.

The product of its digits is 918540, while the sum is 55.

The square root of 9991154791 is about 99955.7641709571. The cubic root of 9991154791 is about 2153.7992884827.

The spelling of 9991154791 in words is "nine billion, nine hundred ninety-one million, one hundred fifty-four thousand, seven hundred ninety-one".