121212225 has 18 divisors (see below), whose sum is σ = 217104966. Its totient is φ = 64646400.

The previous prime is 121212209. The next prime is 121212253. The reversal of 121212225 is 522212121.

It can be written as a sum of positive squares in 3 ways, for example, as 11716929 + 109495296 = 3423^2 + 10464^2 .

It is not a de Polignac number, because 121212225 - 2⁴ = 121212209 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 121212198 and 121212207.

It is an unprimeable number.

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 17 ways as a sum of consecutive naturals, for example, 269136 + ... + 269585.

It is an arithmetic number, because the mean of its divisors is an integer number (12061387).

Almost surely, 2^121212225 is an apocalyptic number.

121212225 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

121212225 is a deficient number, since it is larger than the sum of its proper divisors (95892741).

121212225 is a wasteful number, since it uses less digits than its factorization.

121212225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 538737 (or 538729 counting only the distinct ones).

The product of its digits is 160, while the sum is 18.

The square root of 121212225 is about 11009.6423647637. The cubic root of 121212225 is about 494.8977444119.

Adding to 121212225 its reverse (522212121), we get a palindrome (643424346).

The spelling of 121212225 in words is "one hundred twenty-one million, two hundred twelve thousand, two hundred twenty-five".