261316311311 has 64 divisors (see below), whose sum is σ = 308448000000. Its totient is φ = 218889216000.

The previous prime is 261316311301. The next prime is 261316311331. The reversal of 261316311311 is 113113613162.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 261316311311 - 2²² = 261312117007 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261316311301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 581996015 + ... + 581996463.

It is an arithmetic number, because the mean of its divisors is an integer number (4819500000).

Almost surely, 2^261316311311 is an apocalyptic number.

261316311311 is a deficient number, since it is larger than the sum of its proper divisors (47131688689).

261316311311 is a wasteful number, since it uses less digits than its factorization.

261316311311 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1008.

The product of its digits is 1944, while the sum is 29.

Adding to 261316311311 its reverse (113113613162), we get a palindrome (374429924473).

The spelling of 261316311311 in words is "two hundred sixty-one billion, three hundred sixteen million, three hundred eleven thousand, three hundred eleven".