261687131146741 has 2 divisors, whose sum is σ = 261687131146742. Its totient is φ = 261687131146740.

The previous prime is 261687131146729. The next prime is 261687131146817. The reversal of 261687131146741 is 147641131786162.

It is a happy number.

261687131146741 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., 261413763207025 + 273367939716 = 16168295^2 + 522846^2 .

It is a cyclic number.

It is not a de Polignac number, because 261687131146741 - 2¹⁵ = 261687131113973 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261687131156741) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130843565573370 + 130843565573371.

It is an arithmetic number, because the mean of its divisors is an integer number (130843565573371).

Almost surely, 2^{261687131146741} is an apocalyptic number.

It is an amenable number.

261687131146741 is a deficient number, since it is larger than the sum of its proper divisors (1).

261687131146741 is an equidigital number, since it uses as much as digits as its factorization.

261687131146741 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8128512, while the sum is 58.

The spelling of 261687131146741 in words is "two hundred sixty-one trillion, six hundred eighty-seven billion, one hundred thirty-one million, one hundred forty-six thousand, seven hundred forty-one".