8509009081 has 2 divisors, whose sum is σ = 8509009082. Its totient is φ = 8509009080.

The previous prime is 8509009063. The next prime is 8509009123. The reversal of 8509009081 is 1809009058.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8291741481 + 217267600 = 91059^2 + 14740^2 .

It is a cyclic number.

It is not a de Polignac number, because 8509009081 - 2⁵ = 8509009049 is a prime.

It is a super-2 number, since 2×8509009081² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (8509006081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4254504540 + 4254504541.

It is an arithmetic number, because the mean of its divisors is an integer number (4254504541).

Almost surely, 2^8509009081 is an apocalyptic number.

It is an amenable number.

8509009081 is a deficient number, since it is larger than the sum of its proper divisors (1).

8509009081 is an equidigital number, since it uses as much as digits as its factorization.

8509009081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 25920, while the sum is 40.

The square root of 8509009081 is about 92244.2902352227. The cubic root of 8509009081 is about 2041.5483152261.

The spelling of 8509009081 in words is "eight billion, five hundred nine million, nine thousand, eighty-one".