261085871 has 2 divisors, whose sum is σ = 261085872. Its totient is φ = 261085870.

The previous prime is 261085831. The next prime is 261085883. The reversal of 261085871 is 178580162.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 261085871 - 2¹⁰ = 261084847 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261085831) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130542935 + 130542936.

It is an arithmetic number, because the mean of its divisors is an integer number (130542936).

Almost surely, 2^261085871 is an apocalyptic number.

261085871 is a deficient number, since it is larger than the sum of its proper divisors (1).

261085871 is an equidigital number, since it uses as much as digits as its factorization.

261085871 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 26880, while the sum is 38.

The square root of 261085871 is about 16158.1518435742. The cubic root of 261085871 is about 639.1377312067.

The spelling of 261085871 in words is "two hundred sixty-one million, eighty-five thousand, eight hundred seventy-one".