1225531121 has 2 divisors, whose sum is σ = 1225531122. Its totient is φ = 1225531120.

The previous prime is 1225531093. The next prime is 1225531127. The reversal of 1225531121 is 1211355221.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 653364721 + 572166400 = 25561^2 + 23920^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1225531121 is a prime.

It is not a weakly prime, because it can be changed into another prime (1225531127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 612765560 + 612765561.

It is an arithmetic number, because the mean of its divisors is an integer number (612765561).

Almost surely, 2^1225531121 is an apocalyptic number.

It is an amenable number.

1225531121 is a deficient number, since it is larger than the sum of its proper divisors (1).

1225531121 is an equidigital number, since it uses as much as digits as its factorization.

1225531121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 600, while the sum is 23.

The square root of 1225531121 is about 35007.5866206170. The cubic root of 1225531121 is about 1070.1420957241.

Adding to 1225531121 its reverse (1211355221), we get a palindrome (2436886342).

The spelling of 1225531121 in words is "one billion, two hundred twenty-five million, five hundred thirty-one thousand, one hundred twenty-one".