21003322020 has 96 divisors (see below), whose sum is σ = 59844863232. Its totient is φ = 5502855168.

The previous prime is 21003321973. The next prime is 21003322037. The reversal of 21003322020 is 2022330012.

It is a super-2 number, since 2×21003322020² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1142824 + ... + 1161056.

It is an arithmetic number, because the mean of its divisors is an integer number (623383992).

Almost surely, 2^21003322020 is an apocalyptic number.

21003322020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21003322020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29922431616).

21003322020 is an abundant number, since it is smaller than the sum of its proper divisors (38841541212).

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

21003322020 is a wasteful number, since it uses less digits than its factorization.

21003322020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18581 (or 18579 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 15.

Adding to 21003322020 its reverse (2022330012), we get a palindrome (23025652032).

The spelling of 21003322020 in words is "twenty-one billion, three million, three hundred twenty-two thousand, twenty".