261096801681 has 64 divisors (see below), whose sum is σ = 386488972800. Its totient is φ = 156039561216.

The previous prime is 261096801631. The next prime is 261096801701. The reversal of 261096801681 is 186108690162.

It is not a de Polignac number, because 261096801681 - 2¹¹ = 261096799633 is a prime.

It is a super-2 number, since 2×261096801681² (a number of 24 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 261096801681.

It is not an unprimeable number, because it can be changed into a prime (261096801631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 64102261 + ... + 64106333.

It is an arithmetic number, because the mean of its divisors is an integer number (6038890200).

Almost surely, 2^261096801681 is an apocalyptic number.

It is an amenable number.

261096801681 is a deficient number, since it is larger than the sum of its proper divisors (125392171119).

261096801681 is a wasteful number, since it uses less digits than its factorization.

261096801681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4698.

The product of its (nonzero) digits is 248832, while the sum is 48.

The spelling of 261096801681 in words is "two hundred sixty-one billion, ninety-six million, eight hundred one thousand, six hundred eighty-one".