1205522861 has 2 divisors, whose sum is σ = 1205522862. Its totient is φ = 1205522860.

The previous prime is 1205522783. The next prime is 1205522891. The reversal of 1205522861 is 1682255021.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1166222500 + 39300361 = 34150^2 + 6269^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1205522861 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1205522891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 602761430 + 602761431.

It is an arithmetic number, because the mean of its divisors is an integer number (602761431).

Almost surely, 2^1205522861 is an apocalyptic number.

It is an amenable number.

1205522861 is a deficient number, since it is larger than the sum of its proper divisors (1).

1205522861 is an equidigital number, since it uses as much as digits as its factorization.

1205522861 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9600, while the sum is 32.

The square root of 1205522861 is about 34720.6402734742. The cubic root of 1205522861 is about 1064.2863288634.

Adding to 1205522861 its reverse (1682255021), we get a palindrome (2887777882).

The spelling of 1205522861 in words is "one billion, two hundred five million, five hundred twenty-two thousand, eight hundred sixty-one".