21212110000 has 100 divisors (see below), whose sum is σ = 51513066792. Its totient is φ = 8459008000.

The previous prime is 21212109967. The next prime is 21212110013. The reversal of 21212110000 is 1121212.

It is a tau number, because it is divible by the number of its divisors (100).

It is a super-3 number, since 3×21212110000³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

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

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 3466944 + ... + 3473056.

Almost surely, 2^21212110000 is an apocalyptic number.

21212110000 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 21212110000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25756533396).

21212110000 is an abundant number, since it is smaller than the sum of its proper divisors (30300956792).

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

21212110000 is an equidigital number, since it uses as much as digits as its factorization.

21212110000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6488 (or 6467 counting only the distinct ones).

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

Adding to 21212110000 its reverse (1121212), we get a palindrome (21213231212).

The spelling of 21212110000 in words is "twenty-one billion, two hundred twelve million, one hundred ten thousand".