21202442123 has 2 divisors, whose sum is σ = 21202442124. Its totient is φ = 21202442122.

The previous prime is 21202442119. The next prime is 21202442141. The reversal of 21202442123 is 32124420212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21202442123 - 2² = 21202442119 is a prime.

It is not a weakly prime, because it can be changed into another prime (21202442113) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10601221061 + 10601221062.

It is an arithmetic number, because the mean of its divisors is an integer number (10601221062).

Almost surely, 2^21202442123 is an apocalyptic number.

21202442123 is a deficient number, since it is larger than the sum of its proper divisors (1).

21202442123 is an equidigital number, since it uses as much as digits as its factorization.

21202442123 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1536, while the sum is 23.

Adding to 21202442123 its reverse (32124420212), we get a palindrome (53326862335).

The spelling of 21202442123 in words is "twenty-one billion, two hundred two million, four hundred forty-two thousand, one hundred twenty-three".