21311101123 has 8 divisors (see below), whose sum is σ = 23016182000. Its totient is φ = 19615415328.

The previous prime is 21311101121. The next prime is 21311101127. The reversal of 21311101123 is 32110111312.

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 21311101123 - 2¹ = 21311101121 is a prime.

It is a super-2 number, since 2×21311101123² (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 = 21311101097 and 21311101106.

It is not an unprimeable number, because it can be changed into a prime (21311101121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2344053 + ... + 2353126.

It is an arithmetic number, because the mean of its divisors is an integer number (2877022750).

Almost surely, 2^21311101123 is an apocalyptic number.

21311101123 is a deficient number, since it is larger than the sum of its proper divisors (1705080877).

21311101123 is a wasteful number, since it uses less digits than its factorization.

21311101123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4697541.

The product of its (nonzero) digits is 36, while the sum is 16.

Adding to 21311101123 its reverse (32110111312), we get a palindrome (53421212435).

The spelling of 21311101123 in words is "twenty-one billion, three hundred eleven million, one hundred one thousand, one hundred twenty-three".