810649181 has 2 divisors, whose sum is σ = 810649182. Its totient is φ = 810649180.

The previous prime is 810649111. The next prime is 810649183. The reversal of 810649181 is 181946018.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 658743556 + 151905625 = 25666^2 + 12325^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-810649181 is a prime.

It is a super-2 number, since 2×810649181² = 1314304189311941522, which contains 22 as substring.

Together with 810649183, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (810649183) 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, 405324590 + 405324591.

It is an arithmetic number, because the mean of its divisors is an integer number (405324591).

Almost surely, 2^810649181 is an apocalyptic number.

It is an amenable number.

810649181 is a deficient number, since it is larger than the sum of its proper divisors (1).

810649181 is an equidigital number, since it uses as much as digits as its factorization.

810649181 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13824, while the sum is 38.

The square root of 810649181 is about 28471.9016049157. The cubic root of 810649181 is about 932.4187169289.

The spelling of 810649181 in words is "eight hundred ten million, six hundred forty-nine thousand, one hundred eighty-one".