1242440 has 32 divisors (see below), whose sum is σ = 2835000. Its totient is φ = 489984.

The previous prime is 1242421. The next prime is 1242457. The reversal of 1242440 is 442421.

It can be written as a sum of positive squares in 4 ways, for example, as 948676 + 293764 = 974^2 + 542^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3386 + ... + 3734.

2^1242440 is an apocalyptic number.

1242440 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 1242440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1417500).

1242440 is an abundant number, since it is smaller than the sum of its proper divisors (1592560).

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

1242440 is a wasteful number, since it uses less digits than its factorization.

1242440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 449 (or 445 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 17.

The square root of 1242440 is about 1114.6479264772. The cubic root of 1242440 is about 107.5041281991.

Adding to 1242440 its reverse (442421), we get a palindrome (1684861).

The spelling of 1242440 in words is "one million, two hundred forty-two thousand, four hundred forty".