261546220441 has 4 divisors (see below), whose sum is σ = 285323149584. Its totient is φ = 237769291300.

The previous prime is 261546220427. The next prime is 261546220477. The reversal of 261546220441 is 144022645162.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 261546220441 - 2⁵ = 261546220409 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 261546220441.

It is not an unprimeable number, because it can be changed into a prime (261546220421) 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 3 ways as a sum of consecutive naturals, for example, 11888464555 + ... + 11888464576.

It is an arithmetic number, because the mean of its divisors is an integer number (71330787396).

Almost surely, 2^261546220441 is an apocalyptic number.

It is an amenable number.

261546220441 is a deficient number, since it is larger than the sum of its proper divisors (23776929143).

261546220441 is a wasteful number, since it uses less digits than its factorization.

261546220441 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23776929142.

The product of its (nonzero) digits is 92160, while the sum is 37.

The spelling of 261546220441 in words is "two hundred sixty-one billion, five hundred forty-six million, two hundred twenty thousand, four hundred forty-one".