261646244226271 has 2 divisors, whose sum is σ = 261646244226272. Its totient is φ = 261646244226270.

The previous prime is 261646244226247. The next prime is 261646244226379. The reversal of 261646244226271 is 172622442646162.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 261646244226271 - 2¹¹ = 261646244224223 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261646244223271) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130823122113135 + 130823122113136.

It is an arithmetic number, because the mean of its divisors is an integer number (130823122113136).

Almost surely, 2^{261646244226271} is an apocalyptic number.

261646244226271 is a deficient number, since it is larger than the sum of its proper divisors (1).

261646244226271 is an equidigital number, since it uses as much as digits as its factorization.

261646244226271 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18579456, while the sum is 55.

The spelling of 261646244226271 in words is "two hundred sixty-one trillion, six hundred forty-six billion, two hundred forty-four million, two hundred twenty-six thousand, two hundred seventy-one".