21220212020 has 48 divisors (see below), whose sum is σ = 50962722048. Its totient is φ = 7270613760.

The previous prime is 21220212011. The next prime is 21220212053. The reversal of 21220212020 is 2021202212.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is a junction number, because it is equal to n+sod(n) for n = 21220211986 and 21220212004.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 161384 + ... + 261696.

It is an arithmetic number, because the mean of its divisors is an integer number (1061723376).

Almost surely, 2^21220212020 is an apocalyptic number.

21220212020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21220212020 is an abundant number, since it is smaller than the sum of its proper divisors (29742510028).

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

21220212020 is a wasteful number, since it uses less digits than its factorization.

21220212020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101840 (or 101838 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 14.

Adding to 21220212020 its reverse (2021202212), we get a palindrome (23241414232).

The spelling of 21220212020 in words is "twenty-one billion, two hundred twenty million, two hundred twelve thousand, twenty".