It is an Ulam number.
It is a congruent number.
It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 61776.
It is an unprimeable number.
61776 is an untouchable number, because it is not equal to the sum of proper divisors of any number.
261776 is an apocalyptic number.
61776 is a gapful number since it is divisible by the number (66) formed by its first and last digit.
It is an amenable number.
It is a practical number, because each smaller number is the sum of distinct divisors of 61776, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (104160).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
61776 is a wasteful number, since it uses less digits than its factorization.
61776 is an odious number, because the sum of its binary digits is odd.
The square root of 61776 is about 248.5477821265. The cubic root of 61776 is about 39.5311936472.
The spelling of 61776 in words is "sixty-one thousand, seven hundred seventy-six".