1211206625 has 16 divisors (see below), whose sum is σ = 1548460368. Its totient is φ = 945328000.

The previous prime is 1211206621. The next prime is 1211206643. The reversal of 1211206625 is 5266021121.

It can be written as a sum of positive squares in 8 ways, for example, as 667757281 + 543449344 = 25841^2 + 23312^2 .

It is not a de Polignac number, because 1211206625 - 2² = 1211206621 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1211206594 and 1211206603.

It is not an unprimeable number, because it can be changed into a prime (1211206621) 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 in 15 ways as a sum of consecutive naturals, for example, 113042 + ... + 123291.

It is an arithmetic number, because the mean of its divisors is an integer number (96778773).

Almost surely, 2^1211206625 is an apocalyptic number.

It is an amenable number.

1211206625 is a deficient number, since it is larger than the sum of its proper divisors (337253743).

1211206625 is an equidigital number, since it uses as much as digits as its factorization.

1211206625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 236389 (or 236379 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 26.

The square root of 1211206625 is about 34802.3939550141. The cubic root of 1211206625 is about 1065.9563290908.

Adding to 1211206625 its reverse (5266021121), we get a palindrome (6477227746).

The spelling of 1211206625 in words is "one billion, two hundred eleven million, two hundred six thousand, six hundred twenty-five".