212121022020 has 48 divisors (see below), whose sum is σ = 600061959168. Its totient is φ = 55982453760.

The previous prime is 212121021977. The next prime is 212121022021. The reversal of 212121022020 is 20220121212.

212121022020 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is a super-3 number, since 3×212121022020³ (a number of 35 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is not an unprimeable number, because it can be changed into a prime (212121022021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18217636 + ... + 18229275.

It is an arithmetic number, because the mean of its divisors is an integer number (12501290816).

Almost surely, 2^212121022020 is an apocalyptic number.

212121022020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

212121022020 is an abundant number, since it is smaller than the sum of its proper divisors (387940937148).

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

212121022020 is a wasteful number, since it uses less digits than its factorization.

212121022020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36447020 (or 36447018 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 212121022020 its reverse (20220121212), we get a palindrome (232341143232).

The spelling of 212121022020 in words is "two hundred twelve billion, one hundred twenty-one million, twenty-two thousand, twenty".