1212120211 has 4 divisors (see below), whose sum is σ = 1213137432. Its totient is φ = 1211102992.

The previous prime is 1212120199. The next prime is 1212120223. The reversal of 1212120211 is 1120212121.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (1212120199) and next prime (1212120223).

It is a cyclic number.

It is not a de Polignac number, because 1212120211 - 2¹⁹ = 1211595923 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1212120191 and 1212120200.

It is not an unprimeable number, because it can be changed into a prime (1212120011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 506821 + ... + 509206.

It is an arithmetic number, because the mean of its divisors is an integer number (303284358).

Almost surely, 2^1212120211 is an apocalyptic number.

1212120211 is a deficient number, since it is larger than the sum of its proper divisors (1017221).

1212120211 is a wasteful number, since it uses less digits than its factorization.

1212120211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1017220.

The product of its (nonzero) digits is 16, while the sum is 13.

The square root of 1212120211 is about 34815.5168136278. The cubic root of 1212120211 is about 1066.2242707208.

Adding to 1212120211 its reverse (1120212121), we get a palindrome (2332332332).

The spelling of 1212120211 in words is "one billion, two hundred twelve million, one hundred twenty thousand, two hundred eleven".