1311242545 has 4 divisors (see below), whose sum is σ = 1573491060. Its totient is φ = 1048994032.

The previous prime is 1311242539. The next prime is 1311242551. The reversal of 1311242545 is 5452421131.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5452421131 = 79 ⋅69017989.

It is an interprime number because it is at equal distance from previous prime (1311242539) and next prime (1311242551).

It can be written as a sum of positive squares in 2 ways, for example, as 633629584 + 677612961 = 25172^2 + 26031^2 .

It is a cyclic number.

It is not a de Polignac number, because 1311242545 - 2²¹ = 1309145393 is a prime.

It is an unprimeable number.

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, 131124250 + ... + 131124259.

It is an arithmetic number, because the mean of its divisors is an integer number (393372765).

Almost surely, 2^1311242545 is an apocalyptic number.

It is an amenable number.

1311242545 is a deficient number, since it is larger than the sum of its proper divisors (262248515).

1311242545 is an equidigital number, since it uses as much as digits as its factorization.

1311242545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 262248514.

The product of its digits is 4800, while the sum is 28.

The square root of 1311242545 is about 36211.0831790489. The cubic root of 1311242545 is about 1094.5300193928.

Adding to 1311242545 its reverse (5452421131), we get a palindrome (6763663676).

It can be divided in two parts, 131 and 1242545, that added together give a triangular number (1242676 = T₁₅₇₆).

The spelling of 1311242545 in words is "one billion, three hundred eleven million, two hundred forty-two thousand, five hundred forty-five".