21103110011 has 4 divisors (see below), whose sum is σ = 21501281952. Its totient is φ = 20704938072.

The previous prime is 21103110001. The next prime is 21103110023. The reversal of 21103110011 is 11001130112.

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 21103110011 - 2⁶ = 21103109947 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21103109974 and 21103110001.

It is not an unprimeable number, because it can be changed into a prime (21103110001) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 199085891 + ... + 199085996.

It is an arithmetic number, because the mean of its divisors is an integer number (5375320488).

Almost surely, 2^21103110011 is an apocalyptic number.

21103110011 is a deficient number, since it is larger than the sum of its proper divisors (398171941).

21103110011 is an equidigital number, since it uses as much as digits as its factorization.

21103110011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 398171940.

The product of its (nonzero) digits is 6, while the sum is 11.

Adding to 21103110011 its reverse (11001130112), we get a palindrome (32104240123).

The spelling of 21103110011 in words is "twenty-one billion, one hundred three million, one hundred ten thousand, eleven".