21033331213123 has 2 divisors, whose sum is σ = 21033331213124. Its totient is φ = 21033331213122.

The previous prime is 21033331213109. The next prime is 21033331213151. The reversal of 21033331213123 is 32131213333012.

It is a happy number.

It is an a-pointer prime, because the next prime (21033331213151) can be obtained adding 21033331213123 to its sum of digits (28).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21033331213123 - 2⁹ = 21033331212611 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21033331213091 and 21033331213100.

It is not a weakly prime, because it can be changed into another prime (21033331213183) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10516665606561 + 10516665606562.

It is an arithmetic number, because the mean of its divisors is an integer number (10516665606562).

Almost surely, 2^{21033331213123} is an apocalyptic number.

21033331213123 is a deficient number, since it is larger than the sum of its proper divisors (1).

21033331213123 is an equidigital number, since it uses as much as digits as its factorization.

21033331213123 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5832, while the sum is 28.

Adding to 21033331213123 its reverse (32131213333012), we get a palindrome (53164544546135).

It can be divided in two parts, 210 and 33331213123, that added together give a palindrome (33331213333).

The spelling of 21033331213123 in words is "twenty-one trillion, thirty-three billion, three hundred thirty-one million, two hundred thirteen thousand, one hundred twenty-three".