261976668529 has 16 divisors (see below), whose sum is σ = 265093920000. Its totient is φ = 258881261760.

The previous prime is 261976668517. The next prime is 261976668589. The reversal of 261976668529 is 925866679162.

It is a cyclic number.

It is not a de Polignac number, because 261976668529 - 2¹⁵ = 261976635761 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261976668589) 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 15 ways as a sum of consecutive naturals, for example, 30215607 + ... + 30224275.

It is an arithmetic number, because the mean of its divisors is an integer number (16568370000).

Almost surely, 2^261976668529 is an apocalyptic number.

It is an amenable number.

261976668529 is a deficient number, since it is larger than the sum of its proper divisors (3117251471).

261976668529 is a wasteful number, since it uses less digits than its factorization.

261976668529 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9888.

The product of its digits is 117573120, while the sum is 67.

The spelling of 261976668529 in words is "two hundred sixty-one billion, nine hundred seventy-six million, six hundred sixty-eight thousand, five hundred twenty-nine".