806856561 has 36 divisors (see below), whose sum is σ = 1376409216. Its totient is φ = 446154480.

The previous prime is 806856493. The next prime is 806856563. The reversal of 806856561 is 165658608.

806856561 is a `hidden beast` number, since 8 + 0 + 6 + 85 + 6 + 561 = 666.

806856561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 806856561 - 2⁷ = 806856433 is a prime.

It is not an unprimeable number, because it can be changed into a prime (806856563) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 53880 + ... + 67206.

Almost surely, 2^806856561 is an apocalyptic number.

It is an amenable number.

806856561 is a deficient number, since it is larger than the sum of its proper divisors (569552655).

806856561 is a wasteful number, since it uses less digits than its factorization.

806856561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13402 (or 13368 counting only the distinct ones).

The product of its (nonzero) digits is 345600, while the sum is 45.

The square root of 806856561 is about 28405.2206645187. The cubic root of 806856561 is about 930.9623371911.

The spelling of 806856561 in words is "eight hundred six million, eight hundred fifty-six thousand, five hundred sixty-one".