21130311011 has 2 divisors, whose sum is σ = 21130311012. Its totient is φ = 21130311010.

The previous prime is 21130310969. The next prime is 21130311029. The reversal of 21130311011 is 11011303112.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21130311011 is a prime.

It is not a weakly prime, because it can be changed into another prime (21130311031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10565155505 + 10565155506.

It is an arithmetic number, because the mean of its divisors is an integer number (10565155506).

Almost surely, 2^21130311011 is an apocalyptic number.

21130311011 is a deficient number, since it is larger than the sum of its proper divisors (1).

21130311011 is an equidigital number, since it uses as much as digits as its factorization.

21130311011 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 18, while the sum is 14.

Adding to 21130311011 its reverse (11011303112), we get a palindrome (32141614123).

The spelling of 21130311011 in words is "twenty-one billion, one hundred thirty million, three hundred eleven thousand, eleven".