828220781 has 2 divisors, whose sum is σ = 828220782. Its totient is φ = 828220780.

The previous prime is 828220747. The next prime is 828220817. The reversal of 828220781 is 187022828.

Together with next prime (828220817) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 699602500 + 128618281 = 26450^2 + 11341^2 .

It is a cyclic number.

It is not a de Polignac number, because 828220781 - 2¹⁴ = 828204397 is a prime.

It is a super-2 number, since 2×828220781² = 1371899324160499922, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (828220381) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 414110390 + 414110391.

It is an arithmetic number, because the mean of its divisors is an integer number (414110391).

Almost surely, 2^828220781 is an apocalyptic number.

It is an amenable number.

828220781 is a deficient number, since it is larger than the sum of its proper divisors (1).

828220781 is an equidigital number, since it uses as much as digits as its factorization.

828220781 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 28672, while the sum is 38.

The square root of 828220781 is about 28778.8252192476. The cubic root of 828220781 is about 939.1076415174.

The spelling of 828220781 in words is "eight hundred twenty-eight million, two hundred twenty thousand, seven hundred eighty-one".