1801500 has 48 divisors (see below), whose sum is σ = 5250336. Its totient is φ = 480000.

The previous prime is 1801489. The next prime is 1801517. The reversal of 1801500 is 51081.

It is a happy number.

1801500 is an esthetic number in base 7, because in such base its adjacent digits differ by 1.

It is a Harshad number since it is a multiple of its sum of digits (15).

1801500 is an undulating number in base 7.

It is a self number, because there is not a number n which added to its sum of digits gives 1801500.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 900 + ... + 2100.

It is an arithmetic number, because the mean of its divisors is an integer number (109382).

2^1801500 is an apocalyptic number.

1801500 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 1801500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2625168).

1801500 is an abundant number, since it is smaller than the sum of its proper divisors (3448836).

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

1801500 is a wasteful number, since it uses less digits than its factorization.

1801500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1223 (or 1211 counting only the distinct ones).

The product of its (nonzero) digits is 40, while the sum is 15.

The square root of 1801500 is about 1342.1996870809. The cubic root of 1801500 is about 121.6778205408.

Adding to 1801500 its reverse (51081), we get a palindrome (1852581).

The spelling of 1801500 in words is "one million, eight hundred one thousand, five hundred".