856901 has 2 divisors, whose sum is σ = 856902. Its totient is φ = 856900.

The previous prime is 856897. The next prime is 856903. The reversal of 856901 is 109658.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 763876 + 93025 = 874^2 + 305^2 .

It is a cyclic number.

It is not a de Polignac number, because 856901 - 2² = 856897 is a prime.

Together with 856903, it forms a pair of twin primes.

It is a Chen prime.

It is an alternating number because its digits alternate between even and odd.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (856903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 428450 + 428451.

It is an arithmetic number, because the mean of its divisors is an integer number (428451).

2⁸⁵⁶⁹⁰¹ is an apocalyptic number.

It is an amenable number.

856901 is a deficient number, since it is larger than the sum of its proper divisors (1).

856901 is an equidigital number, since it uses as much as digits as its factorization.

856901 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2160, while the sum is 29.

The square root of 856901 is about 925.6894727715. The cubic root of 856901 is about 94.9824898476.

The spelling of 856901 in words is "eight hundred fifty-six thousand, nine hundred one".