21323002123 has 2 divisors, whose sum is σ = 21323002124. Its totient is φ = 21323002122.

The previous prime is 21323002109. The next prime is 21323002163. The reversal of 21323002123 is 32120032312.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21323002123 - 2²¹ = 21320904971 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21323002123.

It is not a weakly prime, because it can be changed into another prime (21323002163) 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 as a sum of consecutive naturals, namely, 10661501061 + 10661501062.

It is an arithmetic number, because the mean of its divisors is an integer number (10661501062).

Almost surely, 2^21323002123 is an apocalyptic number.

21323002123 is a deficient number, since it is larger than the sum of its proper divisors (1).

21323002123 is an equidigital number, since it uses as much as digits as its factorization.

21323002123 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 432, while the sum is 19.

Adding to 21323002123 its reverse (32120032312), we get a palindrome (53443034435).

The spelling of 21323002123 in words is "twenty-one billion, three hundred twenty-three million, two thousand, one hundred twenty-three".