21001100101120 has 80 divisors (see below), whose sum is σ = 50686886197728. Its totient is φ = 8344807833600.

The previous prime is 21001100101097. The next prime is 21001100101187. The reversal of 21001100101120 is 2110100110012.

It is a tau number, because it is divible by the number of its divisors (80).

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

It is a junction number, because it is equal to n+sod(n) for n = 21001100101097 and 21001100101106.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26777529 + ... + 27550648.

Almost surely, 2^{21001100101120} is an apocalyptic number.

21001100101120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21001100101120 is an abundant number, since it is smaller than the sum of its proper divisors (29685786096608).

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

21001100101120 is an equidigital number, since it uses as much as digits as its factorization.

21001100101120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54328351 (or 54328335 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 10.

Adding to 21001100101120 its reverse (2110100110012), we get a palindrome (23111200211132).

The spelling of 21001100101120 in words is "twenty-one trillion, one billion, one hundred million, one hundred one thousand, one hundred twenty".