8227781 has 2 divisors, whose sum is σ = 8227782. Its totient is φ = 8227780.

The previous prime is 8227777. The next prime is 8227787. The reversal of 8227781 is 1877228.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5452225 + 2775556 = 2335^2 + 1666^2 .

It is a cyclic number.

It is not a de Polignac number, because 8227781 - 2² = 8227777 is a prime.

It is a super-2 number, since 2×8227781² = 135392760367922, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8227787) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4113890 + 4113891.

It is an arithmetic number, because the mean of its divisors is an integer number (4113891).

Almost surely, 2^8227781 is an apocalyptic number.

It is an amenable number.

8227781 is a deficient number, since it is larger than the sum of its proper divisors (1).

8227781 is an equidigital number, since it uses as much as digits as its factorization.

8227781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12544, while the sum is 35.

The square root of 8227781 is about 2868.4108840959. The cubic root of 8227781 is about 201.8804393286.

The spelling of 8227781 in words is "eight million, two hundred twenty-seven thousand, seven hundred eighty-one".