21331312013123 has 48 divisors (see below), whose sum is σ = 26269849774080. Its totient is φ = 17243291923200.

The previous prime is 21331312013107. The next prime is 21331312013153. The reversal of 21331312013123 is 32131021313312.

It is not a de Polignac number, because 21331312013123 - 2⁴ = 21331312013107 is a prime.

It is a super-2 number, since 2×21331312013123² (a number of 27 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 = 21331312013092 and 21331312013101.

It is not an unprimeable number, because it can be changed into a prime (21331312013153) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 28302203 + ... + 29046123.

It is an arithmetic number, because the mean of its divisors is an integer number (547288536960).

Almost surely, 2^{21331312013123} is an apocalyptic number.

21331312013123 is a deficient number, since it is larger than the sum of its proper divisors (4938537760957).

21331312013123 is a wasteful number, since it uses less digits than its factorization.

21331312013123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 744448 (or 744441 counting only the distinct ones).

The product of its (nonzero) digits is 1944, while the sum is 26.

Adding to 21331312013123 its reverse (32131021313312), we get a palindrome (53462333326435).

The spelling of 21331312013123 in words is "twenty-one trillion, three hundred thirty-one billion, three hundred twelve million, thirteen thousand, one hundred twenty-three".