261342331 has 2 divisors, whose sum is σ = 261342332. Its totient is φ = 261342330.

The previous prime is 261342313. The next prime is 261342371. The reversal of 261342331 is 133243162.

Together with previous prime (261342313) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 261342331 - 2⁵ = 261342299 is a prime.

It is a super-2 number, since 2×261342331² = 136599627945027122, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 261342296 and 261342305.

It is not a weakly prime, because it can be changed into another prime (261342371) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130671165 + 130671166.

It is an arithmetic number, because the mean of its divisors is an integer number (130671166).

Almost surely, 2^261342331 is an apocalyptic number.

261342331 is a deficient number, since it is larger than the sum of its proper divisors (1).

261342331 is an equidigital number, since it uses as much as digits as its factorization.

261342331 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2592, while the sum is 25.

The square root of 261342331 is about 16166.0858280537. The cubic root of 261342331 is about 639.3469339254.

Adding to 261342331 its reverse (133243162), we get a palindrome (394585493).

It can be divided in two parts, 2613 and 42331, that added together give a palindrome (44944).

The spelling of 261342331 in words is "two hundred sixty-one million, three hundred forty-two thousand, three hundred thirty-one".