261030 has 64 divisors (see below), whose sum is σ = 787968. Its totient is φ = 53760.

The previous prime is 261017. The next prime is 261031. The reversal of 261030 is 30162.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 260997 and 261015.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2254 + ... + 2366.

It is an arithmetic number, because the mean of its divisors is an integer number (12312).

2²⁶¹⁰³⁰ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261030, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (393984).

261030 is an abundant number, since it is smaller than the sum of its proper divisors (526938).

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

261030 is a wasteful number, since it uses less digits than its factorization.

261030 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 141.

The product of its (nonzero) digits is 36, while the sum is 12.

The square root of 261030 is about 510.9109511451. The cubic root of 261030 is about 63.9092137253.

Adding to 261030 its reverse (30162), we get a palindrome (291192).

The spelling of 261030 in words is "two hundred sixty-one thousand, thirty".