261641306 has 8 divisors (see below), whose sum is σ = 405995220. Its totient is φ = 126309568.

The previous prime is 261641297. The next prime is 261641309. The reversal of 261641306 is 603146162.

It is a happy number.

261641306 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 255712081 + 5929225 = 15991^2 + 2435^2 .

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

It is a Harshad number since it is a multiple of its sum of digits (29).

It is not an unprimeable number, because it can be changed into a prime (261641309) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2255471 + ... + 2255586.

Almost surely, 2^261641306 is an apocalyptic number.

261641306 is a deficient number, since it is larger than the sum of its proper divisors (144353914).

261641306 is a wasteful number, since it uses less digits than its factorization.

261641306 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4511088.

The product of its (nonzero) digits is 5184, while the sum is 29.

The square root of 261641306 is about 16175.3301666457. The cubic root of 261641306 is about 639.5906448006.

Adding to 261641306 its reverse (603146162), we get a palindrome (864787468).

The spelling of 261641306 in words is "two hundred sixty-one million, six hundred forty-one thousand, three hundred six".