21101220011011 has 4 divisors (see below), whose sum is σ = 24115680012592. Its totient is φ = 18086760009432.

The previous prime is 21101220011009. The next prime is 21101220011041. The reversal of 21101220011011 is 11011002210112.

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 21101220011011 - 2¹ = 21101220011009 is a prime.

It is a super-2 number, since 2×21101220011011² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21101220010982 and 21101220011000.

It is not an unprimeable number, because it can be changed into a prime (21101220011041) 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, 1507230000780 + ... + 1507230000793.

It is an arithmetic number, because the mean of its divisors is an integer number (6028920003148).

Almost surely, 2^{21101220011011} is an apocalyptic number.

21101220011011 is a deficient number, since it is larger than the sum of its proper divisors (3014460001581).

21101220011011 is an equidigital number, since it uses as much as digits as its factorization.

21101220011011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3014460001580.

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

Adding to 21101220011011 its reverse (11011002210112), we get a palindrome (32112222221123).

The spelling of 21101220011011 in words is "twenty-one trillion, one hundred one billion, two hundred twenty million, eleven thousand, eleven".