21101101023 has 4 divisors (see below), whose sum is σ = 28134801368.
Its totient is φ = 14067400680.
The previous prime is 21101101009. The next prime is 21101101027. The reversal of 21101101023 is 32010110112.
Adding to 21101101023 its reverse (32010110112), we get a palindrome (53111211135).
It is a semiprime because it is the product of two primes.
It is not a de Polignac number, because 21101101023 - 212 = 21101096927 is a prime.
It is a Duffinian number.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (21101101027) 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, 3516850168 + ... + 3516850173.
It is an arithmetic number, because the mean of its divisors is an integer number (7033700342).
Almost surely, 221101101023 is an apocalyptic number.
21101101023 is a deficient number, since it is larger than the sum of its proper divisors (7033700345).
21101101023 is an equidigital number, since it uses as much as digits as its factorization.
21101101023 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 7033700344.
The product of its (nonzero) digits is 12, while the sum is 12.
The spelling of 21101101023 in words is "twenty-one billion, one hundred one million, one hundred one thousand, twenty-three".