1311256655 has 4 divisors (see below), whose sum is σ = 1573507992. Its totient is φ = 1049005320.

The previous prime is 1311256649. The next prime is 1311256673. The reversal of 1311256655 is 5566521131.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5566521131 = 433 ⋅12855707.

It is not a de Polignac number, because 1311256655 - 2⁶ = 1311256591 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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, 131125661 + ... + 131125670.

It is an arithmetic number, because the mean of its divisors is an integer number (393376998).

Almost surely, 2^1311256655 is an apocalyptic number.

1311256655 is a deficient number, since it is larger than the sum of its proper divisors (262251337).

1311256655 is an equidigital number, since it uses as much as digits as its factorization.

1311256655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 262251336.

The product of its digits is 27000, while the sum is 35.

The square root of 1311256655 is about 36211.2780083774. The cubic root of 1311256655 is about 1094.5339453797.

Adding to 1311256655 its reverse (5566521131), we get a palindrome (6877777786).

The spelling of 1311256655 in words is "one billion, three hundred eleven million, two hundred fifty-six thousand, six hundred fifty-five".