261006217 has 2 divisors, whose sum is σ = 261006218. Its totient is φ = 261006216.

The previous prime is 261006167. The next prime is 261006247. The reversal of 261006217 is 712600162.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 162282121 + 98724096 = 12739^2 + 9936^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-261006217 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 261006191 and 261006200.

It is not a weakly prime, because it can be changed into another prime (261006247) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130503108 + 130503109.

It is an arithmetic number, because the mean of its divisors is an integer number (130503109).

Almost surely, 2^261006217 is an apocalyptic number.

It is an amenable number.

261006217 is a deficient number, since it is larger than the sum of its proper divisors (1).

261006217 is an equidigital number, since it uses as much as digits as its factorization.

261006217 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1008, while the sum is 25.

The square root of 261006217 is about 16155.6868315773. The cubic root of 261006217 is about 639.0727269805.

Adding to 261006217 its reverse (712600162), we get a palindrome (973606379).

The spelling of 261006217 in words is "two hundred sixty-one million, six thousand, two hundred seventeen".