261560415666 has 32 divisors (see below), whose sum is σ = 570711163968. Its totient is φ = 79256024640.

The previous prime is 261560415661. The next prime is 261560415731. The reversal of 261560415666 is 666514065162.

It is not an unprimeable number, because it can be changed into a prime (261560415661) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1096140 + ... + 1313256.

It is an arithmetic number, because the mean of its divisors is an integer number (17834723874).

Almost surely, 2^261560415666 is an apocalyptic number.

261560415666 is an abundant number, since it is smaller than the sum of its proper divisors (309150748302).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

261560415666 is a wasteful number, since it uses less digits than its factorization.

261560415666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 235386.

The product of its (nonzero) digits is 1555200, while the sum is 48.

The spelling of 261560415666 in words is "two hundred sixty-one billion, five hundred sixty million, four hundred fifteen thousand, six hundred sixty-six".