261788 has 6 divisors (see below), whose sum is σ = 458136. Its totient is φ = 130892.

The previous prime is 261787. The next prime is 261791. The reversal of 261788 is 887162.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261787) 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 as a sum of consecutive naturals, namely, 32720 + ... + 32727.

It is an arithmetic number, because the mean of its divisors is an integer number (76356).

261788 is a Friedman number, since it can be written as 8^6-178*2, using all its digits and the basic arithmetic operations.

2²⁶¹⁷⁸⁸ is an apocalyptic number.

It is an amenable number.

261788 is a deficient number, since it is larger than the sum of its proper divisors (196348).

261788 is a wasteful number, since it uses less digits than its factorization.

261788 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65451 (or 65449 counting only the distinct ones).

The product of its digits is 5376, while the sum is 32.

The square root of 261788 is about 511.6522256377. The cubic root of 261788 is about 63.9710155213.

The spelling of 261788 in words is "two hundred sixty-one thousand, seven hundred eighty-eight".