261776 has 10 divisors (see below), whose sum is σ = 507222. Its totient is φ = 130880.

The previous prime is 261773. The next prime is 261787. The reversal of 261776 is 677162.

261776 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 211600 + 50176 = 460^2 + 224^2 .

It is a nialpdrome in base 4 and base 8.

It is not an unprimeable number, because it can be changed into a prime (261773) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8165 + ... + 8196.

2²⁶¹⁷⁷⁶ is an apocalyptic number.

It is an amenable number.

261776 is a deficient number, since it is larger than the sum of its proper divisors (245446).

261776 is a wasteful number, since it uses less digits than its factorization.

261776 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16369 (or 16363 counting only the distinct ones).

The product of its digits is 3528, while the sum is 29.

The square root of 261776 is about 511.6404987880. The cubic root of 261776 is about 63.9700380587.

The spelling of 261776 in words is "two hundred sixty-one thousand, seven hundred seventy-six".