1212122111021 has 4 divisors (see below), whose sum is σ = 1212519661500. Its totient is φ = 1211724560544.

The previous prime is 1212122110987. The next prime is 1212122111041. The reversal of 1212122111021 is 1201112212121.

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 170214004900 + 1041908106121 = 412570^2 + 1020739^2 .

It is a cyclic number.

It is not a de Polignac number, because 1212122111021 - 2⁶ = 1212122110957 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1212122111041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 198770666 + ... + 198776763.

It is an arithmetic number, because the mean of its divisors is an integer number (303129915375).

Almost surely, 2^{1212122111021} is an apocalyptic number.

It is an amenable number.

1212122111021 is a deficient number, since it is larger than the sum of its proper divisors (397550479).

1212122111021 is an equidigital number, since it uses as much as digits as its factorization.

1212122111021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 397550478.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 1212122111021 its reverse (1201112212121), we get a palindrome (2413234323142).

The spelling of 1212122111021 in words is "one trillion, two hundred twelve billion, one hundred twenty-two million, one hundred eleven thousand, twenty-one".