212021110021 has 16 divisors (see below), whose sum is σ = 247339350400. Its totient is φ = 181670338080.

The previous prime is 212021110019. The next prime is 212021110039. The reversal of 212021110021 is 120011120212.

It is not a de Polignac number, because 212021110021 - 2¹ = 212021110019 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 212021109983 and 212021110010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212021110061) 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, 915025 + ... + 1123081.

It is an arithmetic number, because the mean of its divisors is an integer number (15458709400).

Almost surely, 2^212021110021 is an apocalyptic number.

It is an amenable number.

212021110021 is a deficient number, since it is larger than the sum of its proper divisors (35318240379).

212021110021 is an equidigital number, since it uses as much as digits as its factorization.

212021110021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 211049 (or 211035 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 212021110021 its reverse (120011120212), we get a palindrome (332032230233).

The spelling of 212021110021 in words is "two hundred twelve billion, twenty-one million, one hundred ten thousand, twenty-one".