8861891 has 2 divisors, whose sum is σ = 8861892. Its totient is φ = 8861890.

The previous prime is 8861887. The next prime is 8861893. The reversal of 8861891 is 1981688.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 8861891 - 2² = 8861887 is a prime.

It is a super-2 number, since 2×8861891² = 157066224191762, which contains 22 as substring.

Together with 8861893, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (8861893) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4430945 + 4430946.

It is an arithmetic number, because the mean of its divisors is an integer number (4430946).

Almost surely, 2^8861891 is an apocalyptic number.

8861891 is a deficient number, since it is larger than the sum of its proper divisors (1).

8861891 is an equidigital number, since it uses as much as digits as its factorization.

8861891 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 27648, while the sum is 41.

The square root of 8861891 is about 2976.8928432176. The cubic root of 8861891 is about 206.9388992497.

The spelling of 8861891 in words is "eight million, eight hundred sixty-one thousand, eight hundred ninety-one".