1212121312 has 24 divisors (see below), whose sum is σ = 2410971696. Its totient is φ = 599811072.

The previous prime is 1212121307. The next prime is 1212121331. The reversal of 1212121312 is 2131212121.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 192148 + ... + 198355.

It is an arithmetic number, because the mean of its divisors is an integer number (100457154).

Almost surely, 2^1212121312 is an apocalyptic number.

It is an amenable number.

1212121312 is a deficient number, since it is larger than the sum of its proper divisors (1198850384).

1212121312 is an equidigital number, since it uses as much as digits as its factorization.

1212121312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 390610 (or 390602 counting only the distinct ones).

The product of its digits is 48, while the sum is 16.

The square root of 1212121312 is about 34815.5326255394. The cubic root of 1212121312 is about 1066.2245935471.

Adding to 1212121312 its reverse (2131212121), we get a palindrome (3343333433).

It can be divided in two parts, 12121 and 21312, that added together give a palindrome (33433).

The spelling of 1212121312 in words is "one billion, two hundred twelve million, one hundred twenty-one thousand, three hundred twelve".