1311500 has 48 divisors (see below), whose sum is σ = 2978976. Its totient is φ = 504000.

The previous prime is 1311493. The next prime is 1311503. The reversal of 1311500 is 51131.

It is not an unprimeable number, because it can be changed into a prime (1311503) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21470 + ... + 21530.

It is an arithmetic number, because the mean of its divisors is an integer number (62062).

2^1311500 is an apocalyptic number.

1311500 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1311500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1489488).

1311500 is an abundant number, since it is smaller than the sum of its proper divisors (1667476).

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

1311500 is a wasteful number, since it uses less digits than its factorization.

1311500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 123 (or 111 counting only the distinct ones).

The product of its (nonzero) digits is 15, while the sum is 11.

The square root of 1311500 is about 1145.2074047962. The cubic root of 1311500 is about 109.4601649615.

Adding to 1311500 its reverse (51131), we get a palindrome (1362631).

The spelling of 1311500 in words is "one million, three hundred eleven thousand, five hundred".