2212121220021 has 12 divisors (see below), whose sum is σ = 3220445942272. Its totient is φ = 1463135294376.

The previous prime is 2212121220013. The next prime is 2212121220053. The reversal of 2212121220021 is 1200221212122.

It is a happy number.

2212121220021 is a `hidden beast` number, since 221 + 212 + 12 + 200 + 21 = 666.

It is not a de Polignac number, because 2212121220021 - 2³ = 2212121220013 is a prime.

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 = 2212121219976 and 2212121220003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2212121220721) 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, 967680931 + ... + 967683216.

Almost surely, 2^{2212121220021} is an apocalyptic number.

It is an amenable number.

2212121220021 is a deficient number, since it is larger than the sum of its proper divisors (1008324722251).

2212121220021 is a wasteful number, since it uses less digits than its factorization.

2212121220021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1935364280 (or 1935364277 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 2212121220021 its reverse (1200221212122), we get a palindrome (3412342432143).

The spelling of 2212121220021 in words is "two trillion, two hundred twelve billion, one hundred twenty-one million, two hundred twenty thousand, twenty-one".