809999960 has 128 divisors (see below), whose sum is σ = 2281305600. Its totient is φ = 251458560.

The previous prime is 809999959. The next prime is 809999989. The reversal of 809999960 is 69999908.

It is a self number, because there is not a number n which added to its sum of digits gives 809999960.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1259399 + ... + 1260041.

It is an arithmetic number, because the mean of its divisors is an integer number (17822700).

Almost surely, 2^809999960 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 809999960, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1140652800).

809999960 is an abundant number, since it is smaller than the sum of its proper divisors (1471305640).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

809999960 is a wasteful number, since it uses less digits than its factorization.

809999960 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1081 (or 1077 counting only the distinct ones).

The product of its (nonzero) digits is 2834352, while the sum is 59.

The square root of 809999960 is about 28460.4982387870. The cubic root of 809999960 is about 932.1697364418.

The spelling of 809999960 in words is "eight hundred nine million, nine hundred ninety-nine thousand, nine hundred sixty".