21211011000020 has 24 divisors (see below), whose sum is σ = 44675298553704. Its totient is φ = 8459228123136.

The previous prime is 21211010999963. The next prime is 21211011000029. The reversal of 21211011000020 is 2000011011212.

It can be written as a sum of positive squares in 4 ways, for example, as 3574270049476 + 17636740950544 = 1890574^2 + 4199612^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21211010999965 and 21211011000010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21211011000029) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1573510397 + ... + 1573523876.

It is an arithmetic number, because the mean of its divisors is an integer number (1861470773071).

Almost surely, 2^{21211011000020} is an apocalyptic number.

21211011000020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21211011000020 is an abundant number, since it is smaller than the sum of its proper divisors (23464287553684).

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

21211011000020 is a wasteful number, since it uses less digits than its factorization.

21211011000020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3147034619 (or 3147034617 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 21211011000020 its reverse (2000011011212), we get a palindrome (23211022011232).

The spelling of 21211011000020 in words is "twenty-one trillion, two hundred eleven billion, eleven million, twenty", and thus it is an aban number.