1311403123 has 4 divisors (see below), whose sum is σ = 1380424360. Its totient is φ = 1242381888.

The previous prime is 1311403111. The next prime is 1311403147. The reversal of 1311403123 is 3213041131.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1311403123 - 2⁵ = 1311403091 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (19), and also a Moran number because the ratio is a prime number: 69021217 = 1311403123 / (1 + 3 + 1 + 1 + 4 + 0 + 3 + 1 + 2 + 3).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1311403123.

It is not an unprimeable number, because it can be changed into a prime (1311403153) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34510590 + ... + 34510627.

It is an arithmetic number, because the mean of its divisors is an integer number (345106090).

Almost surely, 2^1311403123 is an apocalyptic number.

1311403123 is a deficient number, since it is larger than the sum of its proper divisors (69021237).

1311403123 is an equidigital number, since it uses as much as digits as its factorization.

1311403123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69021236.

The product of its (nonzero) digits is 216, while the sum is 19.

The square root of 1311403123 is about 36213.3003605029. The cubic root of 1311403123 is about 1094.5746971853.

Adding to 1311403123 its reverse (3213041131), we get a palindrome (4524444254).

The spelling of 1311403123 in words is "one billion, three hundred eleven million, four hundred three thousand, one hundred twenty-three".