21211020001111 has 2 divisors, whose sum is σ = 21211020001112. Its totient is φ = 21211020001110.

The previous prime is 21211020001027. The next prime is 21211020001153. The reversal of 21211020001111 is 11110002011212.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21211020001111 - 2²⁵ = 21210986446679 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21211020001091 and 21211020001100.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21211020001711) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10605510000555 + 10605510000556.

It is an arithmetic number, because the mean of its divisors is an integer number (10605510000556).

Almost surely, 2^{21211020001111} is an apocalyptic number.

21211020001111 is a deficient number, since it is larger than the sum of its proper divisors (1).

21211020001111 is an equidigital number, since it uses as much as digits as its factorization.

21211020001111 is an evil number, because the sum of its binary digits is even.

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

Adding to 21211020001111 its reverse (11110002011212), we get a palindrome (32321022012323).

The spelling of 21211020001111 in words is "twenty-one trillion, two hundred eleven billion, twenty million, one thousand, one hundred eleven".