1668840 has 32 divisors (see below), whose sum is σ = 5006880. Its totient is φ = 444992.

The previous prime is 1668833. The next prime is 1668847. The reversal of 1668840 is 488661.

It is an interprime number because it is at equal distance from previous prime (1668833) and next prime (1668847).

It is not an unprimeable number, because it can be changed into a prime (1668847) 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, 6834 + ... + 7073.

It is an arithmetic number, because the mean of its divisors is an integer number (156465).

2^1668840 is an apocalyptic number.

1668840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1668840 is an abundant number, since it is smaller than the sum of its proper divisors (3338040).

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

1668840 is a wasteful number, since it uses less digits than its factorization.

1668840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13921 (or 13917 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 33.

The square root of 1668840 is about 1291.8359028917. The cubic root of 1668840 is about 118.6146231970.

The spelling of 1668840 in words is "one million, six hundred sixty-eight thousand, eight hundred forty".