1009840 has 40 divisors (see below), whose sum is σ = 2531088. Its totient is φ = 372480.

The previous prime is 1009837. The next prime is 1009843. The reversal of 1009840 is 489001.

1009840 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (1009837) and next prime (1009843).

It is a tau number, because it is divible by the number of its divisors (40).

It is not an unprimeable number, because it can be changed into a prime (1009843) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 555 + ... + 1525.

2^1009840 is an apocalyptic number.

1009840 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 1009840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1265544).

1009840 is an abundant number, since it is smaller than the sum of its proper divisors (1521248).

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

1009840 is a wasteful number, since it uses less digits than its factorization.

1009840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 997 (or 991 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 22.

The square root of 1009840 is about 1004.9079559840. The cubic root of 1009840 is about 100.3269300030.

It can be divided in two parts, 1009 and 840, that added together give a square (1849 = 43²).

The spelling of 1009840 in words is "one million, nine thousand, eight hundred forty".