261696 has 56 divisors (see below), whose sum is σ = 731520. Its totient is φ = 82432.

The previous prime is 261673. The next prime is 261697. The reversal of 261696 is 696162.

Its product of digits (3888) is a multiple of the sum of its prime divisors (81).

It is a nialpdrome in base 4 and base 8.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 261696.

It is not an unprimeable number, because it can be changed into a prime (261697) by changing a digit.

261696 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, 5545 + ... + 5591.

2²⁶¹⁶⁹⁶ 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 261696, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (365760).

261696 is an abundant number, since it is smaller than the sum of its proper divisors (469824).

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

261696 is a wasteful number, since it uses less digits than its factorization.

261696 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91 (or 81 counting only the distinct ones).

The product of its digits is 3888, while the sum is 30.

The square root of 261696 is about 511.5623129199. The cubic root of 261696 is about 63.9635208780.

Adding to 261696 its sum of digits (30), we get a triangular number (261726 = T₇₂₃).

The spelling of 261696 in words is "two hundred sixty-one thousand, six hundred ninety-six".