1668420 has 144 divisors (see below), whose sum is σ = 5870592. Its totient is φ = 380160.

The previous prime is 1668379. The next prime is 1668427. The reversal of 1668420 is 248661.

It is a nialpdrome in base 6.

It is not an unprimeable number, because it can be changed into a prime (1668427) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 53805 + ... + 53835.

It is an arithmetic number, because the mean of its divisors is an integer number (40768).

2^1668420 is an apocalyptic number.

1668420 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 1668420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2935296).

1668420 is an abundant number, since it is smaller than the sum of its proper divisors (4202172).

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

1668420 is a wasteful number, since it uses less digits than its factorization.

1668420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82 (or 77 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 1668420 is about 1291.6733333161. The cubic root of 1668420 is about 118.6046717094.

The spelling of 1668420 in words is "one million, six hundred sixty-eight thousand, four hundred twenty".