21120011111021 has 16 divisors (see below), whose sum is σ = 22291083360000. Its totient is φ = 19954898957376.

The previous prime is 21120011110997. The next prime is 21120011111029. The reversal of 21120011111021 is 12011111002112.

It is a cyclic number.

It is not a de Polignac number, because 21120011111021 - 2²² = 21120006916717 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21120011110987 and 21120011111005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21120011111029) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 72574835 + ... + 72865263.

It is an arithmetic number, because the mean of its divisors is an integer number (1393192710000).

Almost surely, 2^{21120011111021} is an apocalyptic number.

It is an amenable number.

21120011111021 is a deficient number, since it is larger than the sum of its proper divisors (1171072248979).

21120011111021 is a wasteful number, since it uses less digits than its factorization.

21120011111021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 300676.

The product of its (nonzero) digits is 8, while the sum is 14.

Adding to 21120011111021 its reverse (12011111002112), we get a palindrome (33131122113133).

The spelling of 21120011111021 in words is "twenty-one trillion, one hundred twenty billion, eleven million, one hundred eleven thousand, twenty-one".