1243530 has 48 divisors (see below), whose sum is σ = 3321864. Its totient is φ = 322560.

The previous prime is 1243523. The next prime is 1243537. The reversal of 1243530 is 353421.

It is an interprime number because it is at equal distance from previous prime (1243523) and next prime (1243537).

It can be written as a sum of positive squares in 4 ways, for example, as 522729 + 720801 = 723^2 + 849^2 .

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

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1243537) 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, 3522 + ... + 3858.

2^1243530 is an apocalyptic number.

1243530 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 1243530, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1660932).

1243530 is an abundant number, since it is smaller than the sum of its proper divisors (2078334).

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

1243530 is a wasteful number, since it uses less digits than its factorization.

1243530 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 391 (or 388 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 18.

The square root of 1243530 is about 1115.1367629130. The cubic root of 1243530 is about 107.5355570137.

Adding to 1243530 its reverse (353421), we get a palindrome (1596951).

The spelling of 1243530 in words is "one million, two hundred forty-three thousand, five hundred thirty".