261543113 has 32 divisors (see below), whose sum is σ = 316512000. Its totient is φ = 213497856.

The previous prime is 261543103. The next prime is 261543169. The reversal of 261543113 is 311345162.

It is not a de Polignac number, because 261543113 - 2⁸ = 261542857 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (261543103) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 835445 + ... + 835757.

It is an arithmetic number, because the mean of its divisors is an integer number (9891000).

Almost surely, 2^261543113 is an apocalyptic number.

It is an amenable number.

261543113 is a deficient number, since it is larger than the sum of its proper divisors (54968887).

261543113 is a wasteful number, since it uses less digits than its factorization.

261543113 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 561.

The product of its digits is 2160, while the sum is 26.

The square root of 261543113 is about 16172.2946114644. The cubic root of 261543113 is about 639.5106227997.

Adding to 261543113 its reverse (311345162), we get a palindrome (572888275).

The spelling of 261543113 in words is "two hundred sixty-one million, five hundred forty-three thousand, one hundred thirteen".