861470891 has 2 divisors, whose sum is σ = 861470892. Its totient is φ = 861470890.

The previous prime is 861470879. The next prime is 861470893. The reversal of 861470891 is 198074168.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 861470891 - 2¹⁰ = 861469867 is a prime.

Together with 861470893, 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 (861470893) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 430735445 + 430735446.

It is an arithmetic number, because the mean of its divisors is an integer number (430735446).

Almost surely, 2^861470891 is an apocalyptic number.

861470891 is a deficient number, since it is larger than the sum of its proper divisors (1).

861470891 is an equidigital number, since it uses as much as digits as its factorization.

861470891 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 96768, while the sum is 44.

The square root of 861470891 is about 29350.8243666170. The cubic root of 861470891 is about 951.5103918362.

The spelling of 861470891 in words is "eight hundred sixty-one million, four hundred seventy thousand, eight hundred ninety-one".