1233938821 has 2 divisors, whose sum is σ = 1233938822. Its totient is φ = 1233938820.

The previous prime is 1233938819. The next prime is 1233938833. The reversal of 1233938821 is 1288393321.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1005777796 + 228161025 = 31714^2 + 15105^2 .

It is an emirp because it is prime and its reverse (1288393321) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1233938821 - 2¹ = 1233938819 is a prime.

Together with 1233938819, 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 (1233938801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 616969410 + 616969411.

It is an arithmetic number, because the mean of its divisors is an integer number (616969411).

Almost surely, 2^1233938821 is an apocalyptic number.

It is an amenable number.

1233938821 is a deficient number, since it is larger than the sum of its proper divisors (1).

1233938821 is an equidigital number, since it uses as much as digits as its factorization.

1233938821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 62208, while the sum is 40.

The square root of 1233938821 is about 35127.4653369696. The cubic root of 1233938821 is about 1072.5837408510.

The spelling of 1233938821 in words is "one billion, two hundred thirty-three million, nine hundred thirty-eight thousand, eight hundred twenty-one".