261441413 has 2 divisors, whose sum is σ = 261441414. Its totient is φ = 261441412.

The previous prime is 261441407. The next prime is 261441431. The reversal of 261441413 is 314144162.

It is a happy number.

Together with next prime (261441431) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 235868164 + 25573249 = 15358^2 + 5057^2 .

It is a cyclic number.

It is not a de Polignac number, because 261441413 - 2⁸ = 261441157 is a prime.

It is a super-2 number, since 2×261441413² = 136703224862873138, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261441403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130720706 + 130720707.

It is an arithmetic number, because the mean of its divisors is an integer number (130720707).

Almost surely, 2^261441413 is an apocalyptic number.

It is an amenable number.

261441413 is a deficient number, since it is larger than the sum of its proper divisors (1).

261441413 is an equidigital number, since it uses as much as digits as its factorization.

261441413 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2304, while the sum is 26.

The square root of 261441413 is about 16169.1500395042. The cubic root of 261441413 is about 639.4277216656.

Adding to 261441413 its reverse (314144162), we get a palindrome (575585575).

The spelling of 261441413 in words is "two hundred sixty-one million, four hundred forty-one thousand, four hundred thirteen".