1312120121221 has 16 divisors (see below), whose sum is σ = 1626704803584. Its totient is φ = 1030583147904.

The previous prime is 1312120121219. The next prime is 1312120121233. The reversal of 1312120121221 is 1221210212131.

It is a cyclic number.

It is not a de Polignac number, because 1312120121221 - 2¹ = 1312120121219 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1312120101221) 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, 52611265 + ... + 52636198.

It is an arithmetic number, because the mean of its divisors is an integer number (101669050224).

Almost surely, 2^{1312120121221} is an apocalyptic number.

It is an amenable number.

1312120121221 is a deficient number, since it is larger than the sum of its proper divisors (314584682363).

1312120121221 is a wasteful number, since it uses less digits than its factorization.

1312120121221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 105247620.

The product of its (nonzero) digits is 96, while the sum is 19.

Adding to 1312120121221 its reverse (1221210212131), we get a palindrome (2533330333352).

It can be divided in two parts, 1312120 and 121221, that added together give a palindrome (1433341).

The spelling of 1312120121221 in words is "one trillion, three hundred twelve billion, one hundred twenty million, one hundred twenty-one thousand, two hundred twenty-one".