855997 has 2 divisors, whose sum is σ = 855998. Its totient is φ = 855996.

The previous prime is 855989. The next prime is 856021. The reversal of 855997 is 799558.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 549081 + 306916 = 741^2 + 554^2 .

It is a cyclic number.

It is not a de Polignac number, because 855997 - 2³ = 855989 is a prime.

855997 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (855937) 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, 427998 + 427999.

It is an arithmetic number, because the mean of its divisors is an integer number (427999).

2⁸⁵⁵⁹⁹⁷ is an apocalyptic number.

It is an amenable number.

855997 is a deficient number, since it is larger than the sum of its proper divisors (1).

855997 is an equidigital number, since it uses as much as digits as its factorization.

855997 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 113400, while the sum is 43.

The square root of 855997 is about 925.2010592298. The cubic root of 855997 is about 94.9490770484.

The spelling of 855997 in words is "eight hundred fifty-five thousand, nine hundred ninety-seven".