21221102010000 has 400 divisors, whose sum is σ = 68927317797888. Its totient is φ = 5624102400000.

The previous prime is 21221102009999. The next prime is 21221102010001. The reversal of 21221102010000 is 1020112212.

It is an interprime number because it is at equal distance from previous prime (21221102009999) and next prime (21221102010001).

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 (21221102010001) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 8693608780 + ... + 8693611220.

Almost surely, 2^{21221102010000} is an apocalyptic number.

21221102010000 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 21221102010000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34463658898944).

21221102010000 is an abundant number, since it is smaller than the sum of its proper divisors (47706215787888).

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

21221102010000 is a wasteful number, since it uses less digits than its factorization.

21221102010000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4140 (or 4119 counting only the distinct ones).

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

Adding to 21221102010000 its reverse (1020112212), we get a palindrome (21222122122212).

The spelling of 21221102010000 in words is "twenty-one trillion, two hundred twenty-one billion, one hundred two million, ten thousand".