21020112211011 has 16 divisors (see below), whose sum is σ = 29802815007264. Its totient is φ = 13132484470784.

The previous prime is 21020112211001. The next prime is 21020112211013. The reversal of 21020112211011 is 11011221102012.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21020112211011 - 2⁷ = 21020112210883 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21020112211013) 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 15 ways as a sum of consecutive naturals, for example, 884449626 + ... + 884473391.

It is an arithmetic number, because the mean of its divisors is an integer number (1862675937954).

Almost surely, 2^{21020112211011} is an apocalyptic number.

21020112211011 is a deficient number, since it is larger than the sum of its proper divisors (8782702796253).

21020112211011 is a wasteful number, since it uses less digits than its factorization.

21020112211011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1768923270.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 21020112211011 its reverse (11011221102012), we get a palindrome (32031333313023).

The spelling of 21020112211011 in words is "twenty-one trillion, twenty billion, one hundred twelve million, two hundred eleven thousand, eleven".