1280940 has 48 divisors (see below), whose sum is σ = 3689952. Its totient is φ = 331776.

The previous prime is 1280921. The next prime is 1280947. The reversal of 1280940 is 490821.

It is a self number, because there is not a number n which added to its sum of digits gives 1280940.

It is not an unprimeable number, because it can be changed into a prime (1280947) 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 15 ways as a sum of consecutive naturals, for example, 1932 + ... + 2508.

It is an arithmetic number, because the mean of its divisors is an integer number (76874).

2^1280940 is an apocalyptic number.

1280940 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 1280940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1844976).

1280940 is an abundant number, since it is smaller than the sum of its proper divisors (2409012).

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

1280940 is a wasteful number, since it uses less digits than its factorization.

1280940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 626 (or 624 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 24.

The square root of 1280940 is about 1131.7861988909. The cubic root of 1280940 is about 108.6032768327.

The spelling of 1280940 in words is "one million, two hundred eighty thousand, nine hundred forty".