1311005203 has 4 divisors (see below), whose sum is σ = 1311077680. Its totient is φ = 1310932728.

The previous prime is 1311005183. The next prime is 1311005207. The reversal of 1311005203 is 3025001131.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 3025001131 = 17 ⋅177941243.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1311005203 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1311005207) 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 in 3 ways as a sum of consecutive naturals, for example, 15901 + ... + 53617.

It is an arithmetic number, because the mean of its divisors is an integer number (327769420).

Almost surely, 2^1311005203 is an apocalyptic number.

1311005203 is a deficient number, since it is larger than the sum of its proper divisors (72477).

1311005203 is an equidigital number, since it uses as much as digits as its factorization.

1311005203 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72476.

The product of its (nonzero) digits is 90, while the sum is 16.

The square root of 1311005203 is about 36207.8058296826. The cubic root of 1311005203 is about 1094.4639767881.

Adding to 1311005203 its reverse (3025001131), we get a palindrome (4336006334).

The spelling of 1311005203 in words is "one billion, three hundred eleven million, five thousand, two hundred three".