21101131111 has 2 divisors, whose sum is σ = 21101131112. Its totient is φ = 21101131110.

The previous prime is 21101131087. The next prime is 21101131127. The reversal of 21101131111 is 11113110112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21101131111 - 2²¹ = 21099033959 is a prime.

It is a super-2 number, since 2×21101131111² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21101131091 and 21101131100.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21101131411) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10550565555 + 10550565556.

It is an arithmetic number, because the mean of its divisors is an integer number (10550565556).

Almost surely, 2^21101131111 is an apocalyptic number.

21101131111 is a deficient number, since it is larger than the sum of its proper divisors (1).

21101131111 is an equidigital number, since it uses as much as digits as its factorization.

21101131111 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6, while the sum is 13.

Adding to 21101131111 its reverse (11113110112), we get a palindrome (32214241223).

The spelling of 21101131111 in words is "twenty-one billion, one hundred one million, one hundred thirty-one thousand, one hundred eleven".