261768 has 32 divisors (see below), whose sum is σ = 705600. Its totient is φ = 80448.

The previous prime is 261761. The next prime is 261773. The reversal of 261768 is 867162.

It is a happy number.

It is a nialpdrome in base 8.

It is not an unprimeable number, because it can be changed into a prime (261761) by changing a digit.

261768 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

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 in 7 ways as a sum of consecutive naturals, for example, 108 + ... + 731.

It is an arithmetic number, because the mean of its divisors is an integer number (22050).

2²⁶¹⁷⁶⁸ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261768, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (352800).

261768 is an abundant number, since it is smaller than the sum of its proper divisors (443832).

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

261768 is a wasteful number, since it uses less digits than its factorization.

261768 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 861 (or 857 counting only the distinct ones).

The product of its digits is 4032, while the sum is 30.

The square root of 261768 is about 511.6326807388. The cubic root of 261768 is about 63.9693864004.

The spelling of 261768 in words is "two hundred sixty-one thousand, seven hundred sixty-eight".