20021220212020 has 24 divisors (see below), whose sum is σ = 42044666182344. Its totient is φ = 8008468325376.

The previous prime is 20021220211943. The next prime is 20021220212029. The reversal of 20021220212020 is 2021202212002.

It can be written as a sum of positive squares in 4 ways, for example, as 62521001764 + 19958699210256 = 250042^2 + 4467516^2 .

It is a junction number, because it is equal to n+sod(n) for n = 20021220211985 and 20021220212003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20021220212029) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9241212 + ... + 11200108.

It is an arithmetic number, because the mean of its divisors is an integer number (1751861090931).

Almost surely, 2^{20021220212020} is an apocalyptic number.

20021220212020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20021220212020 is an abundant number, since it is smaller than the sum of its proper divisors (22023445970324).

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

20021220212020 is a wasteful number, since it uses less digits than its factorization.

20021220212020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2469939 (or 2469937 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 16.

Adding to 20021220212020 its reverse (2021202212002), we get a palindrome (22042422424022).

The spelling of 20021220212020 in words is "twenty trillion, twenty-one billion, two hundred twenty million, two hundred twelve thousand, twenty".