861268628861 has 2 divisors, whose sum is σ = 861268628862. Its totient is φ = 861268628860.

The previous prime is 861268628819. The next prime is 861268628887. The reversal of 861268628861 is 168826862168.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 806010723961 + 55257904900 = 897781^2 + 235070^2 .

It is a cyclic number.

It is not a de Polignac number, because 861268628861 - 2²² = 861264434557 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 861268628794 and 861268628803.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (861268628161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 430634314430 + 430634314431.

It is an arithmetic number, because the mean of its divisors is an integer number (430634314431).

Almost surely, 2^861268628861 is an apocalyptic number.

It is an amenable number.

861268628861 is a deficient number, since it is larger than the sum of its proper divisors (1).

861268628861 is an equidigital number, since it uses as much as digits as its factorization.

861268628861 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 21233664, while the sum is 62.

The spelling of 861268628861 in words is "eight hundred sixty-one billion, two hundred sixty-eight million, six hundred twenty-eight thousand, eight hundred sixty-one".