861571 has 2 divisors, whose sum is σ = 861572. Its totient is φ = 861570.

The previous prime is 861563. The next prime is 861589. The reversal of 861571 is 175168.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 861571 - 2³ = 861563 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (861541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 430785 + 430786.

It is an arithmetic number, because the mean of its divisors is an integer number (430786).

2⁸⁶¹⁵⁷¹ is an apocalyptic number.

861571 is a deficient number, since it is larger than the sum of its proper divisors (1).

861571 is an equidigital number, since it uses as much as digits as its factorization.

861571 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1680, while the sum is 28.

The square root of 861571 is about 928.2084895108. The cubic root of 861571 is about 95.1547247817.

The spelling of 861571 in words is "eight hundred sixty-one thousand, five hundred seventy-one".