1212021110021 has 16 divisors (see below), whose sum is σ = 1292065806384. Its totient is φ = 1132974895104.

The previous prime is 1212021109997. The next prime is 1212021110051. The reversal of 1212021110021 is 1200111202121.

It can be written as a sum of positive squares in 8 ways, for example, as 195815985121 + 1016205124900 = 442511^2 + 1008070^2 .

It is a cyclic number.

It is not a de Polignac number, because 1212021110021 - 2³⁴ = 1194841240837 is a prime.

It is a super-2 number, since 2×1212021110021² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1212021109978 and 1212021110005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1212021110051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1062761 + ... + 1885073.

It is an arithmetic number, because the mean of its divisors is an integer number (80754112899).

Almost surely, 2^{1212021110021} is an apocalyptic number.

It is an amenable number.

1212021110021 is a deficient number, since it is larger than the sum of its proper divisors (80044696363).

1212021110021 is a wasteful number, since it uses less digits than its factorization.

1212021110021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 822920.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 1212021110021 its reverse (1200111202121), we get a palindrome (2412132312142).

The spelling of 1212021110021 in words is "one trillion, two hundred twelve billion, twenty-one million, one hundred ten thousand, twenty-one".