1311203011 has 4 divisors (see below), whose sum is σ = 1315392472. Its totient is φ = 1307013552.

The previous prime is 1311203009. The next prime is 1311203017. The reversal of 1311203011 is 1103021131.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1103021131 = 349 ⋅3160519.

It is a cyclic number.

It is not a de Polignac number, because 1311203011 - 2¹ = 1311203009 is a prime.

It is a super-2 number, since 2×1311203011² = 3438506672110932242, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1311202982 and 1311203000.

It is not an unprimeable number, because it can be changed into a prime (1311203017) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2094261 + ... + 2094886.

It is an arithmetic number, because the mean of its divisors is an integer number (328848118).

Almost surely, 2^1311203011 is an apocalyptic number.

1311203011 is a deficient number, since it is larger than the sum of its proper divisors (4189461).

1311203011 is an equidigital number, since it uses as much as digits as its factorization.

1311203011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4189460.

The product of its (nonzero) digits is 18, while the sum is 13.

The square root of 1311203011 is about 36210.5372923407. The cubic root of 1311203011 is about 1094.5190192451.

Adding to 1311203011 its reverse (1103021131), we get a palindrome (2414224142).

The spelling of 1311203011 in words is "one billion, three hundred eleven million, two hundred three thousand, eleven".