261830 has 8 divisors (see below), whose sum is σ = 471312. Its totient is φ = 104728.

The previous prime is 261823. The next prime is 261847. The reversal of 261830 is 38162.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 13082 + ... + 13101.

It is an arithmetic number, because the mean of its divisors is an integer number (58914).

2²⁶¹⁸³⁰ is an apocalyptic number.

261830 is a deficient number, since it is larger than the sum of its proper divisors (209482).

261830 is a wasteful number, since it uses less digits than its factorization.

261830 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26190.

The product of its (nonzero) digits is 288, while the sum is 20.

The square root of 261830 is about 511.6932674953. The cubic root of 261830 is about 63.9744364050.

Adding to 261830 its reverse (38162), we get a palindrome (299992).

The spelling of 261830 in words is "two hundred sixty-one thousand, eight hundred thirty".