1225512161 has 2 divisors, whose sum is σ = 1225512162. Its totient is φ = 1225512160.

The previous prime is 1225512157. The next prime is 1225512191. The reversal of 1225512161 is 1612155221.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1201315600 + 24196561 = 34660^2 + 4919^2 .

It is a cyclic number.

It is not a de Polignac number, because 1225512161 - 2² = 1225512157 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1225512161.

It is not a weakly prime, because it can be changed into another prime (1225512121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 612756080 + 612756081.

It is an arithmetic number, because the mean of its divisors is an integer number (612756081).

Almost surely, 2^1225512161 is an apocalyptic number.

It is an amenable number.

1225512161 is a deficient number, since it is larger than the sum of its proper divisors (1).

1225512161 is an equidigital number, since it uses as much as digits as its factorization.

1225512161 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1200, while the sum is 26.

The square root of 1225512161 is about 35007.3158211252. The cubic root of 1225512161 is about 1070.1365770287.

Adding to 1225512161 its reverse (1612155221), we get a palindrome (2837667382).

The spelling of 1225512161 in words is "one billion, two hundred twenty-five million, five hundred twelve thousand, one hundred sixty-one".