21221020110000 has 400 divisors, whose sum is σ = 69235123668480. Its totient is φ = 5598652800000.

The previous prime is 21221020109999. The next prime is 21221020110001. The reversal of 21221020110000 is 1102012212.

It is an interprime number because it is at equal distance from previous prime (21221020109999) and next prime (21221020110001).

It is a tau number, because it is divible by the number of its divisors (400).

It is a Harshad number since it is a multiple of its sum of digits (12).

It is not an unprimeable number, because it can be changed into a prime (21221020110001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 7220488531 + ... + 7220491469.

Almost surely, 2^{21221020110000} is an apocalyptic number.

21221020110000 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 21221020110000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34617561834240).

21221020110000 is an abundant number, since it is smaller than the sum of its proper divisors (48014103558480).

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

21221020110000 is a wasteful number, since it uses less digits than its factorization.

21221020110000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5454 (or 5433 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 21221020110000 its reverse (1102012212), we get a palindrome (21222122122212).

The spelling of 21221020110000 in words is "twenty-one trillion, two hundred twenty-one billion, twenty million, one hundred ten thousand".