1813780 has 24 divisors (see below), whose sum is σ = 3975552. Its totient is φ = 693792.

The previous prime is 1813751. The next prime is 1813789. The reversal of 1813780 is 873181.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1813789) 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 7 ways as a sum of consecutive naturals, for example, 1512 + ... + 2431.

It is an arithmetic number, because the mean of its divisors is an integer number (165648).

2^1813780 is an apocalyptic number.

1813780 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1813780 is an abundant number, since it is smaller than the sum of its proper divisors (2161772).

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

1813780 is a wasteful number, since it uses less digits than its factorization.

1813780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3975 (or 3973 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 28.

The square root of 1813780 is about 1346.7664979498. The cubic root of 1813780 is about 121.9536686923.

The spelling of 1813780 in words is "one million, eight hundred thirteen thousand, seven hundred eighty".