21002221020111 has 32 divisors (see below), whose sum is σ = 28133746467840. Its totient is φ = 13936292632704.

The previous prime is 21002221020107. The next prime is 21002221020127. The reversal of 21002221020111 is 11102012220012.

It is not a de Polignac number, because 21002221020111 - 2² = 21002221020107 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21002221020101) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 820931626 + ... + 820957208.

It is an arithmetic number, because the mean of its divisors is an integer number (879179577120).

Almost surely, 2^{21002221020111} is an apocalyptic number.

21002221020111 is a deficient number, since it is larger than the sum of its proper divisors (7131525447729).

21002221020111 is a wasteful number, since it uses less digits than its factorization.

21002221020111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27535.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21002221020111 its reverse (11102012220012), we get a palindrome (32104233240123).

The spelling of 21002221020111 in words is "twenty-one trillion, two billion, two hundred twenty-one million, twenty thousand, one hundred eleven".