21200121211120 has 40 divisors (see below), whose sum is σ = 49420335400560. Its totient is φ = 8457673674240.

The previous prime is 21200121211099. The next prime is 21200121211127. The reversal of 21200121211120 is 2111212100212.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×21200121211120² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a junction number, because it is equal to n+sod(n) for n = 21200121211094 and 21200121211103.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21200121211127) 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, 349575901 + ... + 349636540.

It is an arithmetic number, because the mean of its divisors is an integer number (1235508385014).

Almost surely, 2^{21200121211120} is an apocalyptic number.

21200121211120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21200121211120 is an abundant number, since it is smaller than the sum of its proper divisors (28220214189440).

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

21200121211120 is a wasteful number, since it uses less digits than its factorization.

21200121211120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 699212833 (or 699212827 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 21200121211120 its reverse (2111212100212), we get a palindrome (23311333311332).

The spelling of 21200121211120 in words is "twenty-one trillion, two hundred billion, one hundred twenty-one million, two hundred eleven thousand, one hundred twenty".