21120100020021 has 8 divisors (see below), whose sum is σ = 28332894915040. Its totient is φ = 13993685902512.

The previous prime is 21120100020017. The next prime is 21120100020029. The reversal of 21120100020021 is 12002000102112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21120100020021 - 2² = 21120100020017 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21120100019979 and 21120100020006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21120100020029) 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 7 ways as a sum of consecutive naturals, for example, 21595193806 + ... + 21595194783.

It is an arithmetic number, because the mean of its divisors is an integer number (3541611864380).

Almost surely, 2^{21120100020021} is an apocalyptic number.

It is an amenable number.

21120100020021 is a deficient number, since it is larger than the sum of its proper divisors (7212794895019).

21120100020021 is a wasteful number, since it uses less digits than its factorization.

21120100020021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43190388755.

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

Adding to 21120100020021 its reverse (12002000102112), we get a palindrome (33122100122133).

The spelling of 21120100020021 in words is "twenty-one trillion, one hundred twenty billion, one hundred million, twenty thousand, twenty-one".