261042673 has 2 divisors, whose sum is σ = 261042674. Its totient is φ = 261042672.

The previous prime is 261042631. The next prime is 261042679. The reversal of 261042673 is 376240162.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 260596449 + 446224 = 16143^2 + 668^2 .

It is a cyclic number.

It is not a de Polignac number, because 261042673 - 2⁹ = 261042161 is a prime.

It is not a weakly prime, because it can be changed into another prime (261042679) 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, 130521336 + 130521337.

It is an arithmetic number, because the mean of its divisors is an integer number (130521337).

Almost surely, 2^261042673 is an apocalyptic number.

It is an amenable number.

261042673 is a deficient number, since it is larger than the sum of its proper divisors (1).

261042673 is an equidigital number, since it uses as much as digits as its factorization.

261042673 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12096, while the sum is 31.

The square root of 261042673 is about 16156.8150636194. The cubic root of 261042673 is about 639.1024797209.

The spelling of 261042673 in words is "two hundred sixty-one million, forty-two thousand, six hundred seventy-three".