261726 has 16 divisors (see below), whose sum is σ = 528528. Its totient is φ = 86400.

The previous prime is 261721. The next prime is 261739. The reversal of 261726 is 627162.

It is a happy number.

261726 is a nontrivial binomial coefficient, being equal to C(724, 2).

It is a junction number, because it is equal to n+sod(n) for n = 261696 and 261705.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261721) by changing a digit.

261726 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 966 + ... + 1206.

It is an arithmetic number, because the mean of its divisors is an integer number (33033).

2²⁶¹⁷²⁶ is an apocalyptic number.

261726 is the 723-rd triangular number and also the 362-nd hexagonal number.

261726 is an abundant number, since it is smaller than the sum of its proper divisors (266802).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

261726 is a wasteful number, since it uses less digits than its factorization.

261726 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 427.

The product of its digits is 1008, while the sum is 24.

The square root of 261726 is about 511.5916340207. The cubic root of 261726 is about 63.9659649764.

Adding to 261726 its reverse (627162), we get a palindrome (888888).

The spelling of 261726 in words is "two hundred sixty-one thousand, seven hundred twenty-six".