21211112020 has 48 divisors (see below), whose sum is σ = 52548830208. Its totient is φ = 7037786880.

The previous prime is 21211112017. The next prime is 21211112147. The reversal of 21211112020 is 2021111212.

It is a super-2 number, since 2×21211112020² (a number of 21 digits) contains 22 as substring.

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, 2439337 + ... + 2448016.

It is an arithmetic number, because the mean of its divisors is an integer number (1094767296).

Almost surely, 2^21211112020 is an apocalyptic number.

21211112020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21211112020 is an abundant number, since it is smaller than the sum of its proper divisors (31337718188).

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

21211112020 is a wasteful number, since it uses less digits than its factorization.

21211112020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4887400 (or 4887398 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21211112020 its reverse (2021111212), we get a palindrome (23232223232).

The spelling of 21211112020 in words is "twenty-one billion, two hundred eleven million, one hundred twelve thousand, twenty".