811972789 has 2 divisors, whose sum is σ = 811972790. Its totient is φ = 811972788.

The previous prime is 811972783. The next prime is 811972829. The reversal of 811972789 is 987279118.

811972789 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 786802500 + 25170289 = 28050^2 + 5017^2 .

It is a cyclic number.

It is not a de Polignac number, because 811972789 - 2³ = 811972781 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (811972781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 405986394 + 405986395.

It is an arithmetic number, because the mean of its divisors is an integer number (405986395).

Almost surely, 2^811972789 is an apocalyptic number.

It is an amenable number.

811972789 is a deficient number, since it is larger than the sum of its proper divisors (1).

811972789 is an equidigital number, since it uses as much as digits as its factorization.

811972789 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 508032, while the sum is 52.

The square root of 811972789 is about 28495.1362341014. The cubic root of 811972789 is about 932.9259177462.

It can be divided in two parts, 8119 and 72789, that added together give a palindrome (80908).

The spelling of 811972789 in words is "eight hundred eleven million, nine hundred seventy-two thousand, seven hundred eighty-nine".