1664128 has 16 divisors (see below), whose sum is σ = 3315510. Its totient is φ = 832000.

The previous prime is 1664123. The next prime is 1664227. The reversal of 1664128 is 8214661.

It can be written as a sum of positive squares in only one way, i.e., 1658944 + 5184 = 1288^2 + 72^2 .

It is a tau number, because it is divible by the number of its divisors (16).

It is a junction number, because it is equal to n+sod(n) for n = 1664096 and 1664105.

It is not an unprimeable number, because it can be changed into a prime (1664123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6373 + ... + 6628.

2^1664128 is an apocalyptic number.

It is an amenable number.

1664128 is a deficient number, since it is larger than the sum of its proper divisors (1651382).

1664128 is an equidigital number, since it uses as much as digits as its factorization.

1664128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13015 (or 13003 counting only the distinct ones).

The product of its digits is 2304, while the sum is 28.

The square root of 1664128 is about 1290.0108526675. The cubic root of 1664128 is about 118.5028811159.

Subtracting from 1664128 its sum of digits (28), we obtain a square (1664100 = 1290²).

Adding to 1664128 its reverse (8214661), we get a palindrome (9878789).

The spelling of 1664128 in words is "one million, six hundred sixty-four thousand, one hundred twenty-eight".