811957 has 2 divisors, whose sum is σ = 811958. Its totient is φ = 811956.

The previous prime is 811933. The next prime is 811961. The reversal of 811957 is 759118.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 749956 + 62001 = 866^2 + 249^2 .

It is a cyclic number.

It is not a de Polignac number, because 811957 - 2¹¹ = 809909 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (811997) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 405978 + 405979.

It is an arithmetic number, because the mean of its divisors is an integer number (405979).

2⁸¹¹⁹⁵⁷ is an apocalyptic number.

It is an amenable number.

811957 is a deficient number, since it is larger than the sum of its proper divisors (1).

811957 is an equidigital number, since it uses as much as digits as its factorization.

811957 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2520, while the sum is 31.

The square root of 811957 is about 901.0865663187. The cubic root of 811957 is about 93.2919870720.

The spelling of 811957 in words is "eight hundred eleven thousand, nine hundred fifty-seven".