1212120121221 has 48 divisors (see below), whose sum is σ = 1842109022208. Its totient is φ = 796404798000.

The previous prime is 1212120121213. The next prime is 1212120121229. The reversal of 1212120121221 is 1221210212121.

It is an interprime number because it is at equal distance from previous prime (1212120121213) and next prime (1212120121229).

It is not a de Polignac number, because 1212120121221 - 2³ = 1212120121213 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1212120121194 and 1212120121203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1212120121229) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 4529956 + ... + 4790066.

It is an arithmetic number, because the mean of its divisors is an integer number (38377271296).

Almost surely, 2^{1212120121221} is an apocalyptic number.

It is an amenable number.

1212120121221 is a deficient number, since it is larger than the sum of its proper divisors (629988900987).

1212120121221 is a wasteful number, since it uses less digits than its factorization.

1212120121221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 260404 (or 260392 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 1212120121221 its reverse (1221210212121), we get a palindrome (2433330333342).

The spelling of 1212120121221 in words is "one trillion, two hundred twelve billion, one hundred twenty million, one hundred twenty-one thousand, two hundred twenty-one".