1820180 has 12 divisors (see below), whose sum is σ = 3822420. Its totient is φ = 728064.

The previous prime is 1820171. The next prime is 1820201. The reversal of 1820180 is 810281.

It can be written as a sum of positive squares in 2 ways, for example, as 538756 + 1281424 = 734^2 + 1132^2 .

It is a Harshad number since it is a multiple of its sum of digits (20), and also a Moran number because the ratio is a prime number: 91009 = 1820180 / (1 + 8 + 2 + 0 + 1 + 8 + 0).

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, 45485 + ... + 45524.

It is an arithmetic number, because the mean of its divisors is an integer number (318535).

2^1820180 is an apocalyptic number.

1820180 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1820180 is an abundant number, since it is smaller than the sum of its proper divisors (2002240).

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

1820180 is a wasteful number, since it uses less digits than its factorization.

1820180 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91018 (or 91016 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 20.

The square root of 1820180 is about 1349.1404671123. The cubic root of 1820180 is about 122.0969398831.

It can be divided in two parts, 18201 and 80, that added together give a palindrome (18281).

The spelling of 1820180 in words is "one million, eight hundred twenty thousand, one hundred eighty".