21011021120011 has 4 divisors (see below), whose sum is σ = 22627253513872. Its totient is φ = 19394788726152.

The previous prime is 21011021119967. The next prime is 21011021120081. The reversal of 21011021120011 is 11002112011012.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 21011021120011 - 2⁷ = 21011021119883 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (13), and also a Moran number because the ratio is a prime number: 1616232393847 = 21011021120011 / (2 + 1 + 0 + 1 + 1 + 0 + 2 + 1 + 1 + 2 + 0 + 0 + 1 + 1).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21011021119973 and 21011021120000.

It is not an unprimeable number, because it can be changed into a prime (21011021120081) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 808116196911 + ... + 808116196936.

It is an arithmetic number, because the mean of its divisors is an integer number (5656813378468).

Almost surely, 2^{21011021120011} is an apocalyptic number.

21011021120011 is a deficient number, since it is larger than the sum of its proper divisors (1616232393861).

21011021120011 is a wasteful number, since it uses less digits than its factorization.

21011021120011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1616232393860.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 21011021120011 its reverse (11002112011012), we get a palindrome (32013133131023).

The spelling of 21011021120011 in words is "twenty-one trillion, eleven billion, twenty-one million, one hundred twenty thousand, eleven".