1311178985 has 8 divisors (see below), whose sum is σ = 1587850440. Its totient is φ = 1039319424.

The previous prime is 1311178951. The next prime is 1311178987. The reversal of 1311178985 is 5898711131.

It can be written as a sum of positive squares in 4 ways, for example, as 393149584 + 918029401 = 19828^2 + 30299^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1311178985 - 2¹⁰ = 1311177961 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1311178987) 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 7 ways as a sum of consecutive naturals, for example, 1202372 + ... + 1203461.

It is an arithmetic number, because the mean of its divisors is an integer number (198481305).

Almost surely, 2^1311178985 is an apocalyptic number.

It is an amenable number.

1311178985 is a deficient number, since it is larger than the sum of its proper divisors (276671455).

1311178985 is a wasteful number, since it uses less digits than its factorization.

1311178985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2405947.

The product of its digits is 60480, while the sum is 44.

The square root of 1311178985 is about 36210.2055365611. The cubic root of 1311178985 is about 1094.5123340168.

The spelling of 1311178985 in words is "one billion, three hundred eleven million, one hundred seventy-eight thousand, nine hundred eighty-five".