21222220002020 has 12 divisors (see below), whose sum is σ = 44566662004284. Its totient is φ = 8488888000800.

The previous prime is 21222220001993. The next prime is 21222220002029. The reversal of 21222220002020 is 2020002222212.

It can be written as a sum of positive squares in 2 ways, for example, as 10437603409984 + 10784616592036 = 3230728^2 + 3283994^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21222220002020.

It is not an unprimeable number, because it can be changed into a prime (21222220002029) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 530555500031 + ... + 530555500070.

It is an arithmetic number, because the mean of its divisors is an integer number (3713888500357).

Almost surely, 2^{21222220002020} is an apocalyptic number.

21222220002020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21222220002020 is an abundant number, since it is smaller than the sum of its proper divisors (23344442002264).

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

21222220002020 is a wasteful number, since it uses less digits than its factorization.

21222220002020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1061111000110 (or 1061111000108 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 17.

Adding to 21222220002020 its reverse (2020002222212), we get a palindrome (23242222224232).

The spelling of 21222220002020 in words is "twenty-one trillion, two hundred twenty-two billion, two hundred twenty million, two thousand, twenty".