261141889 has 2 divisors, whose sum is σ = 261141890. Its totient is φ = 261141888.

The previous prime is 261141887. The next prime is 261141899. The reversal of 261141889 is 988141162.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 228251664 + 32890225 = 15108^2 + 5735^2 .

It is a cyclic number.

It is not a de Polignac number, because 261141889 - 2¹ = 261141887 is a prime.

Together with 261141887, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (261141887) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130570944 + 130570945.

It is an arithmetic number, because the mean of its divisors is an integer number (130570945).

Almost surely, 2^261141889 is an apocalyptic number.

It is an amenable number.

261141889 is a deficient number, since it is larger than the sum of its proper divisors (1).

261141889 is an equidigital number, since it uses as much as digits as its factorization.

261141889 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 27648, while the sum is 40.

The square root of 261141889 is about 16159.8851790475. The cubic root of 261141889 is about 639.1834385915.

The spelling of 261141889 in words is "two hundred sixty-one million, one hundred forty-one thousand, eight hundred eighty-nine".