261421177017211 has 16 divisors (see below), whose sum is σ = 264533234853600. Its totient is φ = 258313025555200.

The previous prime is 261421177017191. The next prime is 261421177017241. The reversal of 261421177017211 is 112710771124162.

It is a cyclic number.

It is not a de Polignac number, because 261421177017211 - 2⁵ = 261421177017179 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261421177017241) 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, 2264878281 + ... + 2264993701.

It is an arithmetic number, because the mean of its divisors is an integer number (16533327178350).

Almost surely, 2^{261421177017211} is an apocalyptic number.

261421177017211 is a deficient number, since it is larger than the sum of its proper divisors (3112057836389).

261421177017211 is a wasteful number, since it uses less digits than its factorization.

261421177017211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 132110.

The product of its (nonzero) digits is 65856, while the sum is 43.

The spelling of 261421177017211 in words is "two hundred sixty-one trillion, four hundred twenty-one billion, one hundred seventy-seven million, seventeen thousand, two hundred eleven".