861050750561 has 2 divisors, whose sum is σ = 861050750562. Its totient is φ = 861050750560.

The previous prime is 861050750557. The next prime is 861050750563. The reversal of 861050750561 is 165057050168.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 795690760225 + 65359990336 = 892015^2 + 255656^2 .

It is a cyclic number.

It is not a de Polignac number, because 861050750561 - 2² = 861050750557 is a prime.

It is a super-2 number, since 2×861050750561² (a number of 25 digits) contains 22 as substring.

Together with 861050750563, 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 (861050750563) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 430525375280 + 430525375281.

It is an arithmetic number, because the mean of its divisors is an integer number (430525375281).

Almost surely, 2^861050750561 is an apocalyptic number.

It is an amenable number.

861050750561 is a deficient number, since it is larger than the sum of its proper divisors (1).

861050750561 is an equidigital number, since it uses as much as digits as its factorization.

861050750561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 252000, while the sum is 44.

The spelling of 861050750561 in words is "eight hundred sixty-one billion, fifty million, seven hundred fifty thousand, five hundred sixty-one".