813770681 has 2 divisors, whose sum is σ = 813770682. Its totient is φ = 813770680.

The previous prime is 813770641. The next prime is 813770717. The reversal of 813770681 is 186077318.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 744198400 + 69572281 = 27280^2 + 8341^2 .

It is a cyclic number.

It is not a de Polignac number, because 813770681 - 2¹⁰ = 813769657 is a prime.

It is a super-2 number, since 2×813770681² = 1324445442510407522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (813770611) 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, 406885340 + 406885341.

It is an arithmetic number, because the mean of its divisors is an integer number (406885341).

Almost surely, 2^813770681 is an apocalyptic number.

It is an amenable number.

813770681 is a deficient number, since it is larger than the sum of its proper divisors (1).

813770681 is an equidigital number, since it uses as much as digits as its factorization.

813770681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 56448, while the sum is 41.

The square root of 813770681 is about 28526.6661388954. Note that the first 3 decimals coincide. The cubic root of 813770681 is about 933.6139800447.

The spelling of 813770681 in words is "eight hundred thirteen million, seven hundred seventy thousand, six hundred eighty-one".