261344505541 has 16 divisors (see below), whose sum is σ = 301823366656. Its totient is φ = 221652619776.

The previous prime is 261344505523. The next prime is 261344505623. The reversal of 261344505541 is 145505443162.

It is not a de Polignac number, because 261344505541 - 2⁵ = 261344505509 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 261344505494 and 261344505503.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261344502541) 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, 3326980 + ... + 3404626.

It is an arithmetic number, because the mean of its divisors is an integer number (18863960416).

Almost surely, 2^261344505541 is an apocalyptic number.

It is an amenable number.

261344505541 is a deficient number, since it is larger than the sum of its proper divisors (40478861115).

261344505541 is an equidigital number, since it uses as much as digits as its factorization.

261344505541 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82708.

The product of its (nonzero) digits is 288000, while the sum is 40.

The spelling of 261344505541 in words is "two hundred sixty-one billion, three hundred forty-four million, five hundred five thousand, five hundred forty-one".