856949 has 2 divisors, whose sum is σ = 856950. Its totient is φ = 856948.

The previous prime is 856943. The next prime is 856969. The reversal of 856949 is 949658.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 734449 + 122500 = 857^2 + 350^2 .

It is a cyclic number.

It is not a de Polignac number, because 856949 - 2⁸ = 856693 is a prime.

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 (856943) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 428474 + 428475.

It is an arithmetic number, because the mean of its divisors is an integer number (428475).

2⁸⁵⁶⁹⁴⁹ is an apocalyptic number.

It is an amenable number.

856949 is a deficient number, since it is larger than the sum of its proper divisors (1).

856949 is an equidigital number, since it uses as much as digits as its factorization.

856949 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 77760, while the sum is 41.

The square root of 856949 is about 925.7153990293. The cubic root of 856949 is about 94.9842633214.

The spelling of 856949 in words is "eight hundred fifty-six thousand, nine hundred forty-nine".