21101100005 has 4 divisors (see below), whose sum is σ = 25321320012. Its totient is φ = 16880880000.

The previous prime is 21101099989. The next prime is 21101100061. The reversal of 21101100005 is 50000110112.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 16548764164 + 4552335841 = 128642^2 + 67471^2 .

It is not a de Polignac number, because 21101100005 - 2⁴ = 21101099989 is a prime.

It is a super-2 number, since 2×21101100005² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2110109996 + ... + 2110110005.

It is an arithmetic number, because the mean of its divisors is an integer number (6330330003).

Almost surely, 2^21101100005 is an apocalyptic number.

It is an amenable number.

21101100005 is a deficient number, since it is larger than the sum of its proper divisors (4220220007).

21101100005 is an equidigital number, since it uses as much as digits as its factorization.

21101100005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4220220006.

The product of its (nonzero) digits is 10, while the sum is 11.

Adding to 21101100005 its reverse (50000110112), we get a palindrome (71101210117).

The spelling of 21101100005 in words is "twenty-one billion, one hundred one million, one hundred thousand, five".