1212121211 has 16 divisors (see below), whose sum is σ = 1418634240. Its totient is φ = 1014068160.

The previous prime is 1212121181. The next prime is 1212121217. The reversal of 1212121211 is 1121212121.

It is a de Polignac number, because none of the positive numbers 2^k-1212121211 is a prime.

It is a super-2 number, since 2×1212121211² = 2938475660312213042, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1212121217) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 119831 + ... + 129551.

It is an arithmetic number, because the mean of its divisors is an integer number (88664640).

Almost surely, 2^1212121211 is an apocalyptic number.

1212121211 is a deficient number, since it is larger than the sum of its proper divisors (206513029).

1212121211 is an equidigital number, since it uses as much as digits as its factorization.

1212121211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10154.

The product of its digits is 16, while the sum is 14.

The square root of 1212121211 is about 34815.5311750374. The cubic root of 1212121211 is about 1066.2245639327.

Adding to 1212121211 its reverse (1121212121), we get a palindrome (2333333332).

It can be divided in two parts, 1 and 212121211, that added together give a palindrome (212121212).

The spelling of 1212121211 in words is "one billion, two hundred twelve million, one hundred twenty-one thousand, two hundred eleven".