21232222020 has 72 divisors (see below), whose sum is σ = 65042129880. Its totient is φ = 5605862400.

The previous prime is 21232222007. The next prime is 21232222027. The reversal of 21232222020 is 2022223212.

It can be written as a sum of positive squares in 4 ways, for example, as 4103171136 + 17129050884 = 64056^2 + 130878^2 .

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 = 21232221984 and 21232222002.

It is not an unprimeable number, because it can be changed into a prime (21232222027) 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 23 ways as a sum of consecutive naturals, for example, 565765 + ... + 602124.

It is an arithmetic number, because the mean of its divisors is an integer number (903362915).

Almost surely, 2^21232222020 is an apocalyptic number.

21232222020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21232222020 is an abundant number, since it is smaller than the sum of its proper divisors (43809907860).

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

21232222020 is a wasteful number, since it uses less digits than its factorization.

21232222020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1168005 (or 1168000 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 18.

Adding to 21232222020 its reverse (2022223212), we get a palindrome (23254445232).

The spelling of 21232222020 in words is "twenty-one billion, two hundred thirty-two million, two hundred twenty-two thousand, twenty".