21212120012122 has 32 divisors (see below), whose sum is σ = 34913171921040. Its totient is φ = 9605236193280.

The previous prime is 21212120012071. The next prime is 21212120012131. The reversal of 21212120012122 is 22121002121212.

It can be written as a sum of positive squares in 8 ways, for example, as 2697868665361 + 18514251346761 = 1642519^2 + 4302819^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21212120012122.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 58506922 + ... + 58868362.

Almost surely, 2^{21212120012122} is an apocalyptic number.

21212120012122 is a deficient number, since it is larger than the sum of its proper divisors (13701051908918).

21212120012122 is a wasteful number, since it uses less digits than its factorization.

21212120012122 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 404098.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 21212120012122 its reverse (22121002121212), we get a palindrome (43333122133334).

The spelling of 21212120012122 in words is "twenty-one trillion, two hundred twelve billion, one hundred twenty million, twelve thousand, one hundred twenty-two".