5281567661 has 2 divisors, whose sum is σ = 5281567662. Its totient is φ = 5281567660.

The previous prime is 5281567601. The next prime is 5281567663. The reversal of 5281567661 is 1667651825.

5281567661 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5235246025 + 46321636 = 72355^2 + 6806^2 .

It is a cyclic number.

It is not a de Polignac number, because 5281567661 - 2⁶ = 5281567597 is a prime.

Together with 5281567663, 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 (5281567663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2640783830 + 2640783831.

It is an arithmetic number, because the mean of its divisors is an integer number (2640783831).

Almost surely, 2^5281567661 is an apocalyptic number.

It is an amenable number.

5281567661 is a deficient number, since it is larger than the sum of its proper divisors (1).

5281567661 is an equidigital number, since it uses as much as digits as its factorization.

5281567661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 604800, while the sum is 47.

The square root of 5281567661 is about 72674.3948100017. The cubic root of 5281567661 is about 1741.4898567621.

The spelling of 5281567661 in words is "five billion, two hundred eighty-one million, five hundred sixty-seven thousand, six hundred sixty-one".