8991694891 has 2 divisors, whose sum is σ = 8991694892. Its totient is φ = 8991694890.

The previous prime is 8991694883. The next prime is 8991694903. The reversal of 8991694891 is 1984961998.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 8991694891 - 2³ = 8991694883 is a prime.

It is not a weakly prime, because it can be changed into another prime (8991694091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4495847445 + 4495847446.

It is an arithmetic number, because the mean of its divisors is an integer number (4495847446).

Almost surely, 2^8991694891 is an apocalyptic number.

8991694891 is a deficient number, since it is larger than the sum of its proper divisors (1).

8991694891 is an equidigital number, since it uses as much as digits as its factorization.

8991694891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10077696, while the sum is 64.

The square root of 8991694891 is about 94824.5479345934. The cubic root of 8991694891 is about 2079.4437993691.

The spelling of 8991694891 in words is "eight billion, nine hundred ninety-one million, six hundred ninety-four thousand, eight hundred ninety-one".