261441431 has 2 divisors, whose sum is σ = 261441432. Its totient is φ = 261441430.

The previous prime is 261441413. The next prime is 261441457. The reversal of 261441431 is 134144162.

It is a happy number.

Together with previous prime (261441413) it forms an Ormiston pair, because they use the same digits, order apart.

It is an a-pointer prime, because the next prime (261441457) can be obtained adding 261441431 to its sum of digits (26).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 261441431 - 2¹⁸ = 261179287 is a prime.

It is a super-2 number, since 2×261441431² = 136703243686655522, which contains 22 as substring.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 261441431.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261441491) 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, 130720715 + 130720716.

It is an arithmetic number, because the mean of its divisors is an integer number (130720716).

Almost surely, 2^261441431 is an apocalyptic number.

261441431 is a deficient number, since it is larger than the sum of its proper divisors (1).

261441431 is an equidigital number, since it uses as much as digits as its factorization.

261441431 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 261441431 is about 16169.1505961198. The cubic root of 261441431 is about 639.4277363402.

Adding to 261441431 its reverse (134144162), we get a palindrome (395585593).

The spelling of 261441431 in words is "two hundred sixty-one million, four hundred forty-one thousand, four hundred thirty-one".