809820011 has 48 divisors (see below), whose sum is σ = 1130734080. Its totient is φ = 569862720.

The previous prime is 809820001. The next prime is 809820013. The reversal of 809820011 is 110028908.

It is a de Polignac number, because none of the positive numbers 2^k-809820011 is a prime.

It is not an unprimeable number, because it can be changed into a prime (809820013) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 328100 + ... + 330558.

It is an arithmetic number, because the mean of its divisors is an integer number (23556960).

Almost surely, 2^809820011 is an apocalyptic number.

809820011 is a deficient number, since it is larger than the sum of its proper divisors (320914069).

809820011 is a wasteful number, since it uses less digits than its factorization.

809820011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2544 (or 2537 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 29.

The square root of 809820011 is about 28457.3366814254. The cubic root of 809820011 is about 932.1007012798.

Adding to 809820011 its reverse (110028908), we get a palindrome (919848919).

The spelling of 809820011 in words is "eight hundred nine million, eight hundred twenty thousand, eleven".