261613 has 8 divisors (see below), whose sum is σ = 302400. Its totient is φ = 223680.

The previous prime is 261601. The next prime is 261619. The reversal of 261613 is 316162.

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

It is a cyclic number.

It is not a de Polignac number, because 261613 - 2⁵ = 261581 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261619) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 513 + ... + 886.

It is an arithmetic number, because the mean of its divisors is an integer number (37800).

2²⁶¹⁶¹³ is an apocalyptic number.

It is an amenable number.

261613 is a deficient number, since it is larger than the sum of its proper divisors (40787).

261613 is a wasteful number, since it uses less digits than its factorization.

261613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1427.

The product of its digits is 216, while the sum is 19.

The square root of 261613 is about 511.4811824496. The cubic root of 261613 is about 63.9567578991.

Adding to 261613 its reverse (316162), we get a palindrome (577775).

The spelling of 261613 in words is "two hundred sixty-one thousand, six hundred thirteen".