261784771 has 2 divisors, whose sum is σ = 261784772. Its totient is φ = 261784770.

The previous prime is 261784753. The next prime is 261784807. The reversal of 261784771 is 177487162.

261784771 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 is a cyclic number.

It is not a de Polignac number, because 261784771 - 2¹³ = 261776579 is a prime.

It is not a weakly prime, because it can be changed into another prime (261784741) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130892385 + 130892386.

It is an arithmetic number, because the mean of its divisors is an integer number (130892386).

Almost surely, 2^261784771 is an apocalyptic number.

261784771 is a deficient number, since it is larger than the sum of its proper divisors (1).

261784771 is an equidigital number, since it uses as much as digits as its factorization.

261784771 is an evil number, because the sum of its binary digits is even.

The product of its digits is 131712, while the sum is 43.

The square root of 261784771 is about 16179.7642442651. The cubic root of 261784771 is about 639.7075250530.

The spelling of 261784771 in words is "two hundred sixty-one million, seven hundred eighty-four thousand, seven hundred seventy-one".