1321240 has 64 divisors (see below), whose sum is σ = 3304800. Its totient is φ = 473088.

The previous prime is 1321219. The next prime is 1321247. The reversal of 1321240 is 421231.

It is a self number, because there is not a number n which added to its sum of digits gives 1321240.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1321247) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19687 + ... + 19753.

2^1321240 is an apocalyptic number.

1321240 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 1321240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1652400).

1321240 is an abundant number, since it is smaller than the sum of its proper divisors (1983560).

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

1321240 is a wasteful number, since it uses less digits than its factorization.

1321240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 124 (or 120 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 1321240 is about 1149.4520433668. The cubic root of 1321240 is about 109.7304695920.

Adding to 1321240 its reverse (421231), we get a palindrome (1742471).

Subtracting from 1321240 its reverse (421231), we obtain a palindrome (900009).

The spelling of 1321240 in words is "one million, three hundred twenty-one thousand, two hundred forty".