261656341057673 has 2 divisors, whose sum is σ = 261656341057674. Its totient is φ = 261656341057672.

The previous prime is 261656341057669. The next prime is 261656341057717. The reversal of 261656341057673 is 376750143656162.

261656341057673 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 171861821913664 + 89794519144009 = 13109608^2 + 9475997^2 .

It is a cyclic number.

It is not a de Polignac number, because 261656341057673 - 2² = 261656341057669 is a prime.

It is not a weakly prime, because it can be changed into another prime (261656341257673) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130828170528836 + 130828170528837.

It is an arithmetic number, because the mean of its divisors is an integer number (130828170528837).

Almost surely, 2^{261656341057673} is an apocalyptic number.

It is an amenable number.

261656341057673 is a deficient number, since it is larger than the sum of its proper divisors (1).

261656341057673 is an equidigital number, since it uses as much as digits as its factorization.

261656341057673 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 114307200, while the sum is 62.

The spelling of 261656341057673 in words is "two hundred sixty-one trillion, six hundred fifty-six billion, three hundred forty-one million, fifty-seven thousand, six hundred seventy-three".