21011120010123 has 4 divisors (see below), whose sum is σ = 28014826680168. Its totient is φ = 14007413340080.

The previous prime is 21011120010043. The next prime is 21011120010187. The reversal of 21011120010123 is 32101002111012.

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 21011120010123 - 2¹⁶ = 21011119944587 is a prime.

It is a super-2 number, since 2×21011120010123² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21011120018123) 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, 3501853335018 + ... + 3501853335023.

It is an arithmetic number, because the mean of its divisors is an integer number (7003706670042).

Almost surely, 2^{21011120010123} is an apocalyptic number.

21011120010123 is a deficient number, since it is larger than the sum of its proper divisors (7003706670045).

21011120010123 is an equidigital number, since it uses as much as digits as its factorization.

21011120010123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7003706670044.

The product of its (nonzero) digits is 24, while the sum is 15.

Adding to 21011120010123 its reverse (32101002111012), we get a palindrome (53112122121135).

The spelling of 21011120010123 in words is "twenty-one trillion, eleven billion, one hundred twenty million, ten thousand, one hundred twenty-three".