21220221022020 has 144 divisors (see below), whose sum is σ = 68136139431360. Its totient is φ = 5336536681728.

The previous prime is 21220221021973. The next prime is 21220221022027. The reversal of 21220221022020 is 2022012202212.

21220221022020 is a `hidden beast` number, since 2 + 1 + 220 + 221 + 0 + 220 + 2 + 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 = 21220221021984 and 21220221022002.

It is not an unprimeable number, because it can be changed into a prime (21220221022027) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 47045034 + ... + 47493953.

It is an arithmetic number, because the mean of its divisors is an integer number (473167634940).

Almost surely, 2^{21220221022020} is an apocalyptic number.

21220221022020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21220221022020 is an abundant number, since it is smaller than the sum of its proper divisors (46915918409340).

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

21220221022020 is a wasteful number, since it uses less digits than its factorization.

21220221022020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94539074 (or 94539069 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

Adding to 21220221022020 its reverse (2022012202212), we get a palindrome (23242233224232).

The spelling of 21220221022020 in words is "twenty-one trillion, two hundred twenty billion, two hundred twenty-one million, twenty-two thousand, twenty".