1801530 has 48 divisors (see below), whose sum is σ = 4819464. Its totient is φ = 466560.

The previous prime is 1801529. The next prime is 1801531. The reversal of 1801530 is 351081.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1801529) and next prime (1801531).

It can be written as a sum of positive squares in 4 ways, for example, as 1656369 + 145161 = 1287^2 + 381^2 .

It is a super-3 number, since 3×1801530³ = 17540652733324731000, which contains 333 as substring.

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 (1801531) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3060 + ... + 3600.

2^1801530 is an apocalyptic number.

1801530 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1801530, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2409732).

1801530 is an abundant number, since it is smaller than the sum of its proper divisors (3017934).

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

1801530 is a wasteful number, since it uses less digits than its factorization.

1801530 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 591 (or 588 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 18.

The square root of 1801530 is about 1342.2108627187. The cubic root of 1801530 is about 121.6784959621.

The spelling of 1801530 in words is "one million, eight hundred one thousand, five hundred thirty".