21113231123 has 8 divisors (see below), whose sum is σ = 21484979040. Its totient is φ = 20742310080.

The previous prime is 21113231077. The next prime is 21113231147. The reversal of 21113231123 is 32113231112.

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 not a de Polignac number, because 21113231123 - 2⁶ = 21113231059 is a prime.

It is a super-2 number, since 2×21113231123² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21113231095 and 21113231104.

It is not an unprimeable number, because it can be changed into a prime (21113231423) 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, 155090 + ... + 257447.

It is an arithmetic number, because the mean of its divisors is an integer number (2685622380).

Almost surely, 2^21113231123 is an apocalyptic number.

21113231123 is a deficient number, since it is larger than the sum of its proper divisors (371747917).

21113231123 is an equidigital number, since it uses as much as digits as its factorization.

21113231123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 413437.

The product of its digits is 216, while the sum is 20.

Adding to 21113231123 its reverse (32113231112), we get a palindrome (53226462235).

The spelling of 21113231123 in words is "twenty-one billion, one hundred thirteen million, two hundred thirty-one thousand, one hundred twenty-three".