21433123 has 2 divisors, whose sum is σ = 21433124. Its totient is φ = 21433122.

The previous prime is 21433103. The next prime is 21433127. The reversal of 21433123 is 32133412.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21433123 - 2¹⁷ = 21302051 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21433123.

It is not a weakly prime, because it can be changed into another prime (21433127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10716561 + 10716562.

It is an arithmetic number, because the mean of its divisors is an integer number (10716562).

Almost surely, 2^21433123 is an apocalyptic number.

21433123 is a deficient number, since it is larger than the sum of its proper divisors (1).

21433123 is an equidigital number, since it uses as much as digits as its factorization.

21433123 is an odious number, because the sum of its binary digits is odd.

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

The square root of 21433123 is about 4629.5920986627. The cubic root of 21433123 is about 277.7762765371.

Adding to 21433123 its reverse (32133412), we get a palindrome (53566535).

The spelling of 21433123 in words is "twenty-one million, four hundred thirty-three thousand, one hundred twenty-three".