21120012120011 has 4 divisors (see below), whose sum is σ = 24137156708592. Its totient is φ = 18102867531432.

The previous prime is 21120012119933. The next prime is 21120012120049. The reversal of 21120012120011 is 11002121002112.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21120012120011 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21120012120061) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1508572294280 + ... + 1508572294293.

It is an arithmetic number, because the mean of its divisors is an integer number (6034289177148).

Almost surely, 2^{21120012120011} is an apocalyptic number.

21120012120011 is a deficient number, since it is larger than the sum of its proper divisors (3017144588581).

21120012120011 is an equidigital number, since it uses as much as digits as its factorization.

21120012120011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3017144588580.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21120012120011 its reverse (11002121002112), we get a palindrome (32122133122123).

The spelling of 21120012120011 in words is "twenty-one trillion, one hundred twenty billion, twelve million, one hundred twenty thousand, eleven".