1311655 has 4 divisors (see below), whose sum is σ = 1573992. Its totient is φ = 1049320.

The previous prime is 1311643. The next prime is 1311689. The reversal of 1311655 is 5561131.

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

It is not a de Polignac number, because 1311655 - 2⁵ = 1311623 is a prime.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 131161 + ... + 131170.

It is an arithmetic number, because the mean of its divisors is an integer number (393498).

2^1311655 is an apocalyptic number.

1311655 is a deficient number, since it is larger than the sum of its proper divisors (262337).

1311655 is an equidigital number, since it uses as much as digits as its factorization.

1311655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 262336.

The product of its digits is 450, while the sum is 22.

The square root of 1311655 is about 1145.2750761280. The cubic root of 1311655 is about 109.4644769852.

Adding to 1311655 its reverse (5561131), we get a palindrome (6872786).

It can be divided in two parts, 1311 and 655, that multiplied together give a triangular number (858705 = T₁₃₁₀).

The spelling of 1311655 in words is "one million, three hundred eleven thousand, six hundred fifty-five".