261870662771 has 2 divisors, whose sum is σ = 261870662772. Its totient is φ = 261870662770.

The previous prime is 261870662743. The next prime is 261870662789. The reversal of 261870662771 is 177266078162.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 261870662771 - 2³⁴ = 244690793587 is a prime.

It is not a weakly prime, because it can be changed into another prime (260870662771) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130935331385 + 130935331386.

It is an arithmetic number, because the mean of its divisors is an integer number (130935331386).

Almost surely, 2^261870662771 is an apocalyptic number.

261870662771 is a deficient number, since it is larger than the sum of its proper divisors (1).

261870662771 is an equidigital number, since it uses as much as digits as its factorization.

261870662771 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2370816, while the sum is 53.

The spelling of 261870662771 in words is "two hundred sixty-one billion, eight hundred seventy million, six hundred sixty-two thousand, seven hundred seventy-one".