261461722779 has 12 divisors (see below), whose sum is σ = 377689817232. Its totient is φ = 174297253200.

The previous prime is 261461722777. The next prime is 261461722807. The reversal of 261461722779 is 977227164162.

261461722779 is a `hidden beast` number, since 2 + 6 + 14 + 617 + 2 + 2 + 7 + 7 + 9 = 666.

261461722779 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 261461722779 - 2¹ = 261461722777 is a prime.

It is not an unprimeable number, because it can be changed into a prime (261461722777) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 721887 + ... + 1021784.

It is an arithmetic number, because the mean of its divisors is an integer number (31474151436).

Almost surely, 2^261461722779 is an apocalyptic number.

261461722779 is a deficient number, since it is larger than the sum of its proper divisors (116228094453).

261461722779 is a wasteful number, since it uses less digits than its factorization.

261461722779 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1760338 (or 1760335 counting only the distinct ones).

The product of its digits is 3556224, while the sum is 54.

The spelling of 261461722779 in words is "two hundred sixty-one billion, four hundred sixty-one million, seven hundred twenty-two thousand, seven hundred seventy-nine".