1811340 has 72 divisors (see below), whose sum is σ = 5700240. Its totient is φ = 465024.

The previous prime is 1811323. The next prime is 1811347. The reversal of 1811340 is 431181.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (1811347) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5047 + ... + 5393.

It is an arithmetic number, because the mean of its divisors is an integer number (79170).

2^1811340 is an apocalyptic number.

1811340 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 1811340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2850120).

1811340 is an abundant number, since it is smaller than the sum of its proper divisors (3888900).

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

1811340 is a wasteful number, since it uses less digits than its factorization.

1811340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 391 (or 386 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 18.

The square root of 1811340 is about 1345.8603196469. The cubic root of 1811340 is about 121.8989578148.

It can be divided in two parts, 181 and 1340, that added together give a square (1521 = 39²).

The spelling of 1811340 in words is "one million, eight hundred eleven thousand, three hundred forty".