212121212101020 has 144 divisors (see below), whose sum is σ = 665259527368800. Its totient is φ = 54667479909888.

The previous prime is 212121212101009. The next prime is 212121212101039. The reversal of 212121212101020 is 20101212121212.

212121212101020 is a `hidden beast` number, since 21 + 212 + 121 + 210 + 102 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 212121212100984 and 212121212101002.

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 47 ways as a sum of consecutive naturals, for example, 105886962 + ... + 107871641.

It is an arithmetic number, because the mean of its divisors is an integer number (4619857828950).

Almost surely, 2^{212121212101020} is an apocalyptic number.

212121212101020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

212121212101020 is an abundant number, since it is smaller than the sum of its proper divisors (453138315267780).

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

212121212101020 is a wasteful number, since it uses less digits than its factorization.

212121212101020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 213758804 (or 213758799 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 212121212101020 its reverse (20101212121212), we get a palindrome (232222424222232).

The spelling of 212121212101020 in words is "two hundred twelve trillion, one hundred twenty-one billion, two hundred twelve million, one hundred one thousand, twenty".