261919715285 has 16 divisors (see below), whose sum is σ = 314614564992. Its totient is φ = 209328609600.

The previous prime is 261919715273. The next prime is 261919715293. The reversal of 261919715285 is 582517919162.

It is not a de Polignac number, because 261919715285 - 2⁴ = 261919715269 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 261919715285.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 33831515 + ... + 33839255.

It is an arithmetic number, because the mean of its divisors is an integer number (19663410312).

Almost surely, 2^261919715285 is an apocalyptic number.

It is an amenable number.

261919715285 is a deficient number, since it is larger than the sum of its proper divisors (52694849707).

261919715285 is a wasteful number, since it uses less digits than its factorization.

261919715285 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13564.

The product of its digits is 2721600, while the sum is 56.

The spelling of 261919715285 in words is "two hundred sixty-one billion, nine hundred nineteen million, seven hundred fifteen thousand, two hundred eighty-five".