1628666 has 16 divisors (see below), whose sum is σ = 2703624. Its totient is φ = 730944.

The previous prime is 1628633. The next prime is 1628689. The reversal of 1628666 is 6668261.

It can be written as a sum of positive squares in 4 ways, for example, as 1357225 + 271441 = 1165^2 + 521^2 .

It is a Smith number, since the sum of its digits (35) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a nialpdrome in base 12.

It is a zygodrome in base 12.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 116 + ... + 1808.

2^1628666 is an apocalyptic number.

1628666 is a deficient number, since it is larger than the sum of its proper divisors (1074958).

1628666 is a wasteful number, since it uses less digits than its factorization.

1628666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1745.

The product of its digits is 20736, while the sum is 35.

The square root of 1628666 is about 1276.1919918257. The cubic root of 1628666 is about 117.6550781690.

It can be divided in two parts, 16 and 28666, that added together give a palindrome (28682).

The spelling of 1628666 in words is "one million, six hundred twenty-eight thousand, six hundred sixty-six".