2121020011221 has 12 divisors (see below), whose sum is σ = 3004166752992. Its totient is φ = 1330836084928.

The previous prime is 2121020011219. The next prime is 2121020011223. The reversal of 2121020011221 is 1221100201212.

It is an interprime number because it is at equal distance from previous prime (2121020011219) and next prime (2121020011223).

It is not a de Polignac number, because 2121020011221 - 2¹ = 2121020011219 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2121020011221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121020011223) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1223194065 + ... + 1223195798.

It is an arithmetic number, because the mean of its divisors is an integer number (250347229416).

Almost surely, 2^{2121020011221} is an apocalyptic number.

It is an amenable number.

2121020011221 is a deficient number, since it is larger than the sum of its proper divisors (883146741771).

2121020011221 is a wasteful number, since it uses less digits than its factorization.

2121020011221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2446389900 (or 2446389883 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 2121020011221 its reverse (1221100201212), we get a palindrome (3342120212433).

The spelling of 2121020011221 in words is "two trillion, one hundred twenty-one billion, twenty million, eleven thousand, two hundred twenty-one".