1243121203 has 2 divisors, whose sum is σ = 1243121204. Its totient is φ = 1243121202.

The previous prime is 1243121197. The next prime is 1243121207. The reversal of 1243121203 is 3021213421.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1243121203 - 2⁵ = 1243121171 is a prime.

It is not a weakly prime, because it can be changed into another prime (1243121207) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 621560601 + 621560602.

It is an arithmetic number, because the mean of its divisors is an integer number (621560602).

Almost surely, 2^1243121203 is an apocalyptic number.

1243121203 is a deficient number, since it is larger than the sum of its proper divisors (1).

1243121203 is an equidigital number, since it uses as much as digits as its factorization.

1243121203 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 1243121203 is about 35257.9239746188. The cubic root of 1243121203 is about 1075.2377200618.

Adding to 1243121203 its reverse (3021213421), we get a palindrome (4264334624).

The spelling of 1243121203 in words is "one billion, two hundred forty-three million, one hundred twenty-one thousand, two hundred three".