21101110123 has 8 divisors (see below), whose sum is σ = 21830353200. Its totient is φ = 20371975008.

The previous prime is 21101110099. The next prime is 21101110207. The reversal of 21101110123 is 32101110112.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21101110123 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21101110523) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 760468 + ... + 787726.

It is an arithmetic number, because the mean of its divisors is an integer number (2728794150).

Almost surely, 2^21101110123 is an apocalyptic number.

21101110123 is a deficient number, since it is larger than the sum of its proper divisors (729243077).

21101110123 is a wasteful number, since it uses less digits than its factorization.

21101110123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53981.

The product of its (nonzero) digits is 12, while the sum is 13.

Adding to 21101110123 its reverse (32101110112), we get a palindrome (53202220235).

The spelling of 21101110123 in words is "twenty-one billion, one hundred one million, one hundred ten thousand, one hundred twenty-three".