581261146861 has 2 divisors, whose sum is σ = 581261146862. Its totient is φ = 581261146860.

The previous prime is 581261146849. The next prime is 581261146889. The reversal of 581261146861 is 168641162185.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 580177749636 + 1083397225 = 761694^2 + 32915^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-581261146861 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (581261186861) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 290630573430 + 290630573431.

It is an arithmetic number, because the mean of its divisors is an integer number (290630573431).

Almost surely, 2^581261146861 is an apocalyptic number.

It is an amenable number.

581261146861 is a deficient number, since it is larger than the sum of its proper divisors (1).

581261146861 is an equidigital number, since it uses as much as digits as its factorization.

581261146861 is an evil number, because the sum of its binary digits is even.

The product of its digits is 552960, while the sum is 49.

The spelling of 581261146861 in words is "five hundred eighty-one billion, two hundred sixty-one million, one hundred forty-six thousand, eight hundred sixty-one".