856894891 has 2 divisors, whose sum is σ = 856894892. Its totient is φ = 856894890.

The previous prime is 856894873. The next prime is 856894903. The reversal of 856894891 is 198498658.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 856894891 - 2⁷ = 856894763 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (856894861) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 428447445 + 428447446.

It is an arithmetic number, because the mean of its divisors is an integer number (428447446).

Almost surely, 2^856894891 is an apocalyptic number.

856894891 is a deficient number, since it is larger than the sum of its proper divisors (1).

856894891 is an equidigital number, since it uses as much as digits as its factorization.

856894891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4976640, while the sum is 58.

The square root of 856894891 is about 29272.7670540385. The cubic root of 856894891 is about 949.8226413133.

The spelling of 856894891 in words is "eight hundred fifty-six million, eight hundred ninety-four thousand, eight hundred ninety-one".