212120210021 has 16 divisors (see below), whose sum is σ = 234520614144. Its totient is φ = 190834009344.

The previous prime is 212120210017. The next prime is 212120210047. The reversal of 212120210021 is 120012021212.

It is a cyclic number.

It is not a de Polignac number, because 212120210021 - 2² = 212120210017 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 212120209978 and 212120210005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212120210821) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 402080 + ... + 765446.

It is an arithmetic number, because the mean of its divisors is an integer number (14657538384).

Almost surely, 2^212120210021 is an apocalyptic number.

It is an amenable number.

212120210021 is a deficient number, since it is larger than the sum of its proper divisors (22400404123).

212120210021 is a wasteful number, since it uses less digits than its factorization.

212120210021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 364900.

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 212120210021 its reverse (120012021212), we get a palindrome (332132231233).

The spelling of 212120210021 in words is "two hundred twelve billion, one hundred twenty million, two hundred ten thousand, twenty-one".