1283840 has 72 divisors (see below), whose sum is σ = 3311280. Its totient is φ = 475136.

The previous prime is 1283839. The next prime is 1283873. The reversal of 1283840 is 483821.

It is a congruent 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, 21731 + ... + 21789.

It is an arithmetic number, because the mean of its divisors is an integer number (45990).

2^1283840 is an apocalyptic number.

1283840 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 1283840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1655640).

1283840 is an abundant number, since it is smaller than the sum of its proper divisors (2027440).

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

1283840 is an equidigital number, since it uses as much as digits as its factorization.

1283840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97 (or 83 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 26.

The square root of 1283840 is about 1133.0666352867. The cubic root of 1283840 is about 108.6851729724.

The spelling of 1283840 in words is "one million, two hundred eighty-three thousand, eight hundred forty".