1211507225 has 6 divisors (see below), whose sum is σ = 1502268990. Its totient is φ = 969205760.

The previous prime is 1211507177. The next prime is 1211507233. The reversal of 1211507225 is 5227051121.

It can be written as a sum of positive squares in 3 ways, for example, as 39677401 + 1171829824 = 6299^2 + 34232^2 .

It is not a de Polignac number, because 1211507225 - 2¹⁸ = 1211245081 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1211507194 and 1211507203.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 24230120 + ... + 24230169.

It is an arithmetic number, because the mean of its divisors is an integer number (250378165).

Almost surely, 2^1211507225 is an apocalyptic number.

It is an amenable number.

1211507225 is a deficient number, since it is larger than the sum of its proper divisors (290761765).

1211507225 is an equidigital number, since it uses as much as digits as its factorization.

1211507225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48460299 (or 48460294 counting only the distinct ones).

The product of its (nonzero) digits is 1400, while the sum is 26.

The square root of 1211507225 is about 34806.7123555213. The cubic root of 1211507225 is about 1066.0445056143.

Adding to 1211507225 its reverse (5227051121), we get a palindrome (6438558346).

The spelling of 1211507225 in words is "one billion, two hundred eleven million, five hundred seven thousand, two hundred twenty-five".