21011322020 has 48 divisors (see below), whose sum is σ = 49583923200. Its totient is φ = 7420718976.

The previous prime is 21011322019. The next prime is 21011322037. The reversal of 21011322020 is 2022311012.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21011321986 and 21011322004.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1750820 + ... + 1762779.

It is an arithmetic number, because the mean of its divisors is an integer number (1032998400).

Almost surely, 2^21011322020 is an apocalyptic number.

21011322020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21011322020 is an abundant number, since it is smaller than the sum of its proper divisors (28572601180).

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

21011322020 is a wasteful number, since it uses less digits than its factorization.

21011322020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3513644 (or 3513642 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 14.

Adding to 21011322020 its reverse (2022311012), we get a palindrome (23033633032).

The spelling of 21011322020 in words is "twenty-one billion, eleven million, three hundred twenty-two thousand, twenty".