203243343421 has 2 divisors, whose sum is σ = 203243343422. Its totient is φ = 203243343420.

The previous prime is 203243343419. The next prime is 203243343451. The reversal of 203243343421 is 124343342302.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 172607842521 + 30635500900 = 415461^2 + 175030^2 .

It is a cyclic number.

It is not a de Polignac number, because 203243343421 - 2¹ = 203243343419 is a prime.

Together with 203243343419, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (203243343451) 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 as a sum of consecutive naturals, namely, 101621671710 + 101621671711.

It is an arithmetic number, because the mean of its divisors is an integer number (101621671711).

Almost surely, 2^203243343421 is an apocalyptic number.

It is an amenable number.

203243343421 is a deficient number, since it is larger than the sum of its proper divisors (1).

203243343421 is an equidigital number, since it uses as much as digits as its factorization.

203243343421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 41472, while the sum is 31.

Adding to 203243343421 its reverse (124343342302), we get a palindrome (327586685723).

The spelling of 203243343421 in words is "two hundred three billion, two hundred forty-three million, three hundred forty-three thousand, four hundred twenty-one".