1666128 has 40 divisors (see below), whose sum is σ = 4358848. Its totient is φ = 548352.

The previous prime is 1666127. The next prime is 1666139. The reversal of 1666128 is 8216661.

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 1666095 and 1666104.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1666127) 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, 4776 + ... + 5112.

2^1666128 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1666128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2179424).

1666128 is an abundant number, since it is smaller than the sum of its proper divisors (2692720).

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

1666128 is a wasteful number, since it uses less digits than its factorization.

1666128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 451 (or 445 counting only the distinct ones).

The product of its digits is 3456, while the sum is 30.

The square root of 1666128 is about 1290.7858071733. The cubic root of 1666128 is about 118.5503355743.

The spelling of 1666128 in words is "one million, six hundred sixty-six thousand, one hundred twenty-eight".