Adding to 261604 its reverse (406162), we get a palindrome (667766).
261604 is an admirable number.
2261604 is an apocalyptic number.
It is an amenable number.
261604 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
261604 is a wasteful number, since it uses less digits than its factorization.
261604 is an odious number, because the sum of its binary digits is odd.
The square root of 261604 is about 511.4723843963. The cubic root of 261604 is about 63.9560244781.
The spelling of 261604 in words is "two hundred sixty-one thousand, six hundred four".