1311780 has 24 divisors (see below), whose sum is σ = 3673152. Its totient is φ = 349792.

The previous prime is 1311773. The next prime is 1311797. The reversal of 1311780 is 871131.

1311780 is nontrivially palindromic in base 11.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10872 + ... + 10991.

It is an arithmetic number, because the mean of its divisors is an integer number (153048).

2^1311780 is an apocalyptic number.

1311780 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1311780 is an abundant number, since it is smaller than the sum of its proper divisors (2361372).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1311780 is a wasteful number, since it uses less digits than its factorization.

1311780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21875 (or 21873 counting only the distinct ones).

The product of its (nonzero) digits is 168, while the sum is 21.

The square root of 1311780 is about 1145.3296468703. The cubic root of 1311780 is about 109.4679541762.

The spelling of 1311780 in words is "one million, three hundred eleven thousand, seven hundred eighty".