21311020000 has 120 divisors (see below), whose sum is σ = 52573602312. Its totient is φ = 8500800000.

The previous prime is 21311019997. The next prime is 21311020039. The reversal of 21311020000 is 2011312.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 8418735 + ... + 8421265.

Almost surely, 2^21311020000 is an apocalyptic number.

21311020000 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 21311020000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26286801156).

21311020000 is an abundant number, since it is smaller than the sum of its proper divisors (31262582312).

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

21311020000 is an equidigital number, since it uses as much as digits as its factorization.

21311020000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2982 (or 2959 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 10.

Adding to 21311020000 its reverse (2011312), we get a palindrome (21313031312).

The spelling of 21311020000 in words is "twenty-one billion, three hundred eleven million, twenty thousand".