212121112121020 has 24 divisors (see below), whose sum is σ = 464821915257504. Its totient is φ = 81159382028736.

The previous prime is 212121112120991. The next prime is 212121112121071. The reversal of 212121112121020 is 20121211121212.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 230566425759 + ... + 230566426678.

It is an arithmetic number, because the mean of its divisors is an integer number (19367579802396).

Almost surely, 2^{212121112121020} is an apocalyptic number.

212121112121020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

212121112121020 is an abundant number, since it is smaller than the sum of its proper divisors (252700803136484).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

212121112121020 is a wasteful number, since it uses less digits than its factorization.

212121112121020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 461132852469 (or 461132852467 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 212121112121020 its reverse (20121211121212), we get a palindrome (232242323242232).

The spelling of 212121112121020 in words is "two hundred twelve trillion, one hundred twenty-one billion, one hundred twelve million, one hundred twenty-one thousand, twenty".