261143567 has 2 divisors, whose sum is σ = 261143568. Its totient is φ = 261143566.

The previous prime is 261143563. The next prime is 261143569. The reversal of 261143567 is 765341162.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 261143567 - 2² = 261143563 is a prime.

Together with 261143569, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261143563) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130571783 + 130571784.

It is an arithmetic number, because the mean of its divisors is an integer number (130571784).

Almost surely, 2^261143567 is an apocalyptic number.

261143567 is a deficient number, since it is larger than the sum of its proper divisors (1).

261143567 is an equidigital number, since it uses as much as digits as its factorization.

261143567 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 30240, while the sum is 35.

The square root of 261143567 is about 16159.9370976499. The cubic root of 261143567 is about 639.1848076397.

The spelling of 261143567 in words is "two hundred sixty-one million, one hundred forty-three thousand, five hundred sixty-seven".