861965617 has 2 divisors, whose sum is σ = 861965618. Its totient is φ = 861965616.

The previous prime is 861965567. The next prime is 861965627. The reversal of 861965617 is 716569168.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 861481201 + 484416 = 29351^2 + 696^2 .

It is a cyclic number.

It is not a de Polignac number, because 861965617 - 2¹¹ = 861963569 is a prime.

It is not a weakly prime, because it can be changed into another prime (861965627) 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, 430982808 + 430982809.

It is an arithmetic number, because the mean of its divisors is an integer number (430982809).

Almost surely, 2^861965617 is an apocalyptic number.

It is an amenable number.

861965617 is a deficient number, since it is larger than the sum of its proper divisors (1).

861965617 is an equidigital number, since it uses as much as digits as its factorization.

861965617 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 544320, while the sum is 49.

The square root of 861965617 is about 29359.2509611536. The cubic root of 861965617 is about 951.6925016254.

The spelling of 861965617 in words is "eight hundred sixty-one million, nine hundred sixty-five thousand, six hundred seventeen".