812364809 has 2 divisors, whose sum is σ = 812364810. Its totient is φ = 812364808.

The previous prime is 812364799. The next prime is 812364841. The reversal of 812364809 is 908463218.

812364809 is nontrivially palindromic in base 11.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 809971600 + 2393209 = 28460^2 + 1547^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-812364809 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (812363809) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 406182404 + 406182405.

It is an arithmetic number, because the mean of its divisors is an integer number (406182405).

Almost surely, 2^812364809 is an apocalyptic number.

It is an amenable number.

812364809 is a deficient number, since it is larger than the sum of its proper divisors (1).

812364809 is an equidigital number, since it uses as much as digits as its factorization.

812364809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 82944, while the sum is 41.

The square root of 812364809 is about 28502.0141218125. The cubic root of 812364809 is about 933.0760322910.

The spelling of 812364809 in words is "eight hundred twelve million, three hundred sixty-four thousand, eight hundred nine".