21101022011 has 2 divisors, whose sum is σ = 21101022012. Its totient is φ = 21101022010.

The previous prime is 21101021987. The next prime is 21101022017. The reversal of 21101022011 is 11022010112.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21101022011 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21101021983 and 21101022001.

It is not a weakly prime, because it can be changed into another prime (21101022017) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10550511005 + 10550511006.

It is an arithmetic number, because the mean of its divisors is an integer number (10550511006).

Almost surely, 2^21101022011 is an apocalyptic number.

21101022011 is a deficient number, since it is larger than the sum of its proper divisors (1).

21101022011 is an equidigital number, since it uses as much as digits as its factorization.

21101022011 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 11.

Adding to 21101022011 its reverse (11022010112), we get a palindrome (32123032123).

The spelling of 21101022011 in words is "twenty-one billion, one hundred one million, twenty-two thousand, eleven".