1312012212121 has 4 divisors (see below), whose sum is σ = 1412936228452. Its totient is φ = 1211088195792.

The previous prime is 1312012212029. The next prime is 1312012212143. The reversal of 1312012212121 is 1212122102131.

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

It can be written as a sum of positive squares in 2 ways, for example, as 329861840896 + 982150371225 = 574336^2 + 991035^2 .

It is a cyclic number.

It is not a de Polignac number, because 1312012212121 - 2²⁷ = 1311877994393 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1312012212191) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 50462008146 + ... + 50462008171.

It is an arithmetic number, because the mean of its divisors is an integer number (353234057113).

Almost surely, 2^{1312012212121} is an apocalyptic number.

It is an amenable number.

1312012212121 is a deficient number, since it is larger than the sum of its proper divisors (100924016331).

1312012212121 is a wasteful number, since it uses less digits than its factorization.

1312012212121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 100924016330.

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

Adding to 1312012212121 its reverse (1212122102131), we get a palindrome (2524134314252).

The spelling of 1312012212121 in words is "one trillion, three hundred twelve billion, twelve million, two hundred twelve thousand, one hundred twenty-one".