2809823 has 2 divisors, whose sum is σ = 2809824. Its totient is φ = 2809822.

The previous prime is 2809813. The next prime is 2809831. The reversal of 2809823 is 3289082.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2809823 - 2⁶ = 2809759 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2809823.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2809813) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1404911 + 1404912.

It is an arithmetic number, because the mean of its divisors is an integer number (1404912).

2^2809823 is an apocalyptic number.

2809823 is a deficient number, since it is larger than the sum of its proper divisors (1).

2809823 is an equidigital number, since it uses as much as digits as its factorization.

2809823 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6912, while the sum is 32.

The square root of 2809823 is about 1676.2526659188. The cubic root of 2809823 is about 141.1106051653.

The spelling of 2809823 in words is "two million, eight hundred nine thousand, eight hundred twenty-three".