261823 has 2 divisors, whose sum is σ = 261824. Its totient is φ = 261822.

The previous prime is 261799. The next prime is 261847. The reversal of 261823 is 328162.

It is a balanced prime because it is at equal distance from previous prime (261799) and next prime (261847).

It is a cyclic number.

It is not a de Polignac number, because 261823 - 2⁵ = 261791 is a prime.

It is a zygodrome in base 4.

It is a junction number, because it is equal to n+sod(n) for n = 261794 and 261803.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130911 + 130912.

It is an arithmetic number, because the mean of its divisors is an integer number (130912).

261823 is a Friedman number, since it can be written as 8^6-322+1, using all its digits and the basic arithmetic operations.

2²⁶¹⁸²³ is an apocalyptic number.

261823 is a deficient number, since it is larger than the sum of its proper divisors (1).

261823 is an equidigital number, since it uses as much as digits as its factorization.

261823 is an evil number, because the sum of its binary digits is even.

The product of its digits is 576, while the sum is 22.

The square root of 261823 is about 511.6864274143. The cubic root of 261823 is about 63.9738662832.

Adding to 261823 its reverse (328162), we get a palindrome (589985).

It can be divided in two parts, 26 and 1823, that added together give a square (1849 = 43²).

The spelling of 261823 in words is "two hundred sixty-one thousand, eight hundred twenty-three".