261550741 has 2 divisors, whose sum is σ = 261550742. Its totient is φ = 261550740.

The previous prime is 261550691. The next prime is 261550759. The reversal of 261550741 is 147055162.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 259886641 + 1664100 = 16121^2 + 1290^2 .

It is a cyclic number.

It is not a de Polignac number, because 261550741 - 2⁷ = 261550613 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261550241) 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, 130775370 + 130775371.

It is an arithmetic number, because the mean of its divisors is an integer number (130775371).

Almost surely, 2^261550741 is an apocalyptic number.

It is an amenable number.

261550741 is a deficient number, since it is larger than the sum of its proper divisors (1).

261550741 is an equidigital number, since it uses as much as digits as its factorization.

261550741 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8400, while the sum is 31.

The square root of 261550741 is about 16172.5304451715. The cubic root of 261550741 is about 639.5168399259.

The spelling of 261550741 in words is "two hundred sixty-one million, five hundred fifty thousand, seven hundred forty-one".