809856986 has 8 divisors (see below), whose sum is σ = 1226813364. Its totient is φ = 400919200.

The previous prime is 809856919. The next prime is 809857001. The reversal of 809856986 is 689658908.

It can be written as a sum of positive squares in 2 ways, for example, as 615784225 + 194072761 = 24815^2 + 13931^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2004395 + ... + 2004798.

Almost surely, 2^809856986 is an apocalyptic number.

809856986 is a deficient number, since it is larger than the sum of its proper divisors (416956378).

809856986 is a wasteful number, since it uses less digits than its factorization.

809856986 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4009296.

The product of its (nonzero) digits is 7464960, while the sum is 59.

The square root of 809856986 is about 28457.9863307297. The cubic root of 809856986 is about 932.1148871065.

The spelling of 809856986 in words is "eight hundred nine million, eight hundred fifty-six thousand, nine hundred eighty-six".