21100023011 has 2 divisors, whose sum is σ = 21100023012. Its totient is φ = 21100023010.

The previous prime is 21100022929. The next prime is 21100023017. The reversal of 21100023011 is 11032000112.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21100023011 is a prime.

It is a super-2 number, since 2×21100023011² (a number of 21 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a junction number, because it is equal to n+sod(n) for n = 21100022983 and 21100023001.

It is not a weakly prime, because it can be changed into another prime (21100023017) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10550011505 + 10550011506.

It is an arithmetic number, because the mean of its divisors is an integer number (10550011506).

Almost surely, 2^21100023011 is an apocalyptic number.

21100023011 is a deficient number, since it is larger than the sum of its proper divisors (1).

21100023011 is an equidigital number, since it uses as much as digits as its factorization.

21100023011 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12, while the sum is 11.

Adding to 21100023011 its reverse (11032000112), we get a palindrome (32132023123).

The spelling of 21100023011 in words is "twenty-one billion, one hundred million, twenty-three thousand, eleven".