1664406 has 12 divisors (see below), whose sum is σ = 3606252. Its totient is φ = 554796.

The previous prime is 1664387. The next prime is 1664407. The reversal of 1664406 is 6044661.

1664406 is a `hidden beast` number, since 16 + 644 + 0 + 6 = 666.

1664406 is nontrivially palindromic in base 8.

1664406 is an undulating number in base 8.

It is a self number, because there is not a number n which added to its sum of digits gives 1664406.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1664407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 46216 + ... + 46251.

It is an arithmetic number, because the mean of its divisors is an integer number (300521).

2^1664406 is an apocalyptic number.

1664406 is an abundant number, since it is smaller than the sum of its proper divisors (1941846).

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

1664406 is a wasteful number, since it uses less digits than its factorization.

1664406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92475 (or 92472 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 1664406 is about 1290.1185991993. The cubic root of 1664406 is about 118.5094795600.

The spelling of 1664406 in words is "one million, six hundred sixty-four thousand, four hundred six".