1566664 has 32 divisors (see below), whose sum is σ = 3376800. Its totient is φ = 673920.

The previous prime is 1566659. The next prime is 1566673. The reversal of 1566664 is 4666651.

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, 1204 + ... + 2140.

It is an arithmetic number, because the mean of its divisors is an integer number (105525).

2^1566664 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 1566664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1688400).

1566664 is an abundant number, since it is smaller than the sum of its proper divisors (1810136).

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

1566664 is a wasteful number, since it uses less digits than its factorization.

1566664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 973 (or 969 counting only the distinct ones).

The product of its digits is 25920, while the sum is 34.

The square root of 1566664 is about 1251.6644917868. The cubic root of 1566664 is about 116.1427098121.

It can be divided in two parts, 1 and 566664, that added together give a palindrome (566665).

The spelling of 1566664 in words is "one million, five hundred sixty-six thousand, six hundred sixty-four".