10685687561 has 2 divisors, whose sum is σ = 10685687562. Its totient is φ = 10685687560.

The previous prime is 10685687543. The next prime is 10685687563. The reversal of 10685687561 is 16578658601.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6606438400 + 4079249161 = 81280^2 + 63869^2 .

It is a cyclic number.

It is not a de Polignac number, because 10685687561 - 2⁶ = 10685687497 is a prime.

It is a super-2 number, since 2×10685687561² (a number of 21 digits) contains 22 as substring.

Together with 10685687563, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (10685687563) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5342843780 + 5342843781.

It is an arithmetic number, because the mean of its divisors is an integer number (5342843781).

Almost surely, 2^10685687561 is an apocalyptic number.

It is an amenable number.

10685687561 is a deficient number, since it is larger than the sum of its proper divisors (1).

10685687561 is an equidigital number, since it uses as much as digits as its factorization.

10685687561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2419200, while the sum is 53.

The spelling of 10685687561 in words is "ten billion, six hundred eighty-five million, six hundred eighty-seven thousand, five hundred sixty-one".