261490612193 has 2 divisors, whose sum is σ = 261490612194. Its totient is φ = 261490612192.

The previous prime is 261490612109. The next prime is 261490612249. The reversal of 261490612193 is 391216094162.

261490612193 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 259032138304 + 2458473889 = 508952^2 + 49583^2 .

It is a cyclic number.

It is not a de Polignac number, because 261490612193 - 2¹⁴ = 261490595809 is a prime.

It is not a weakly prime, because it can be changed into another prime (261490612693) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130745306096 + 130745306097.

It is an arithmetic number, because the mean of its divisors is an integer number (130745306097).

Almost surely, 2^261490612193 is an apocalyptic number.

It is an amenable number.

261490612193 is a deficient number, since it is larger than the sum of its proper divisors (1).

261490612193 is an equidigital number, since it uses as much as digits as its factorization.

261490612193 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 139968, while the sum is 44.

The spelling of 261490612193 in words is "two hundred sixty-one billion, four hundred ninety million, six hundred twelve thousand, one hundred ninety-three".