261888193 has 24 divisors (see below), whose sum is σ = 311413344. Its totient is φ = 219542400.

The previous prime is 261888173. The next prime is 261888199. The reversal of 261888193 is 391888162.

It is not a de Polignac number, because 261888193 - 2⁵ = 261888161 is a prime.

It is a super-3 number, since 3×261888193³ (a number of 26 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261888199) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 791038 + ... + 791368.

It is an arithmetic number, because the mean of its divisors is an integer number (12975556).

Almost surely, 2^261888193 is an apocalyptic number.

It is an amenable number.

261888193 is a deficient number, since it is larger than the sum of its proper divisors (49525151).

261888193 is a wasteful number, since it uses less digits than its factorization.

261888193 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 653 (or 646 counting only the distinct ones).

The product of its digits is 165888, while the sum is 46.

The square root of 261888193 is about 16182.9599579311. The cubic root of 261888193 is about 639.7917559791.

The spelling of 261888193 in words is "two hundred sixty-one million, eight hundred eighty-eight thousand, one hundred ninety-three".