21110012020 has 48 divisors (see below), whose sum is σ = 44797753728. Its totient is φ = 8355209600.

The previous prime is 21110012003. The next prime is 21110012039. The reversal of 21110012020 is 2021001112.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a junction number, because it is equal to n+sod(n) for n = 21110011988 and 21110012006.

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, 5983497 + ... + 5987023.

It is an arithmetic number, because the mean of its divisors is an integer number (933286536).

Almost surely, 2^21110012020 is an apocalyptic number.

21110012020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21110012020 is an abundant number, since it is smaller than the sum of its proper divisors (23687741708).

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

21110012020 is a wasteful number, since it uses less digits than its factorization.

21110012020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6600 (or 6598 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 21110012020 its reverse (2021001112), we get a palindrome (23131013132).

The spelling of 21110012020 in words is "twenty-one billion, one hundred ten million, twelve thousand, twenty".