21002112222011 has 4 divisors (see below), whose sum is σ = 21020047417224. Its totient is φ = 20984177026800.

The previous prime is 21002112221929. The next prime is 21002112222019. The reversal of 21002112222011 is 11022221120012.

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-21002112222011 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21002112222019) 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, 8967595850 + ... + 8967598191.

It is an arithmetic number, because the mean of its divisors is an integer number (5255011854306).

Almost surely, 2^{21002112222011} is an apocalyptic number.

21002112222011 is a deficient number, since it is larger than the sum of its proper divisors (17935195213).

21002112222011 is a wasteful number, since it uses less digits than its factorization.

21002112222011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17935195212.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 21002112222011 its reverse (11022221120012), we get a palindrome (32024333342023).

The spelling of 21002112222011 in words is "twenty-one trillion, two billion, one hundred twelve million, two hundred twenty-two thousand, eleven".