1242240 has 64 divisors (see below), whose sum is σ = 3965760. Its totient is φ = 330752.

The previous prime is 1242233. The next prime is 1242251. The reversal of 1242240 is 422421.

It is a tau number, because it is divible by the number of its divisors (64).

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

It is an Ulam number.

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, 1597 + ... + 2243.

It is an arithmetic number, because the mean of its divisors is an integer number (61965).

2^1242240 is an apocalyptic number.

1242240 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 1242240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1982880).

1242240 is an abundant number, since it is smaller than the sum of its proper divisors (2723520).

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

1242240 is an equidigital number, since it uses as much as digits as its factorization.

1242240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 669 (or 657 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 15.

The square root of 1242240 is about 1114.5582084396. The cubic root of 1242240 is about 107.4983594486.

Adding to 1242240 its reverse (422421), we get a palindrome (1664661).

The spelling of 1242240 in words is "one million, two hundred forty-two thousand, two hundred forty".