260221856617 has 2 divisors, whose sum is σ = 260221856618. Its totient is φ = 260221856616.

The previous prime is 260221856539. The next prime is 260221856651. The reversal of 260221856617 is 716658122062.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 208991608336 + 51230248281 = 457156^2 + 226341^2 .

It is a cyclic number.

It is not a de Polignac number, because 260221856617 - 2³⁵ = 225862118249 is a prime.

It is a super-2 number, since 2×260221856617² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (260221856117) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130110928308 + 130110928309.

It is an arithmetic number, because the mean of its divisors is an integer number (130110928309).

Almost surely, 2^260221856617 is an apocalyptic number.

It is an amenable number.

260221856617 is a deficient number, since it is larger than the sum of its proper divisors (1).

260221856617 is an equidigital number, since it uses as much as digits as its factorization.

260221856617 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 483840, while the sum is 46.

Adding to 260221856617 its reverse (716658122062), we get a palindrome (976879978679).

The spelling of 260221856617 in words is "two hundred sixty billion, two hundred twenty-one million, eight hundred fifty-six thousand, six hundred seventeen".