809356681 has 16 divisors (see below), whose sum is σ = 936633600. Its totient is φ = 685048320.

The previous prime is 809356657. The next prime is 809356697. The reversal of 809356681 is 186653908.

809356681 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-809356681 is a prime.

It is a super-2 number, since 2×809356681² = 1310116474158671522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (809356381) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 188721 + ... + 192961.

It is an arithmetic number, because the mean of its divisors is an integer number (58539600).

Almost surely, 2^809356681 is an apocalyptic number.

It is an amenable number.

809356681 is a deficient number, since it is larger than the sum of its proper divisors (127276919).

809356681 is a wasteful number, since it uses less digits than its factorization.

809356681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4584.

The product of its (nonzero) digits is 311040, while the sum is 46.

The square root of 809356681 is about 28449.1947337706. The cubic root of 809356681 is about 931.9229034969.

It can be divided in two parts, 80935 and 6681, that added together give a square (87616 = 296²).

The spelling of 809356681 in words is "eight hundred nine million, three hundred fifty-six thousand, six hundred eighty-one".