1664556 has 48 divisors (see below), whose sum is σ = 4187904. Its totient is φ = 513216.

The previous prime is 1664549. The next prime is 1664557. The reversal of 1664556 is 6554661.

It is not an unprimeable number, because it can be changed into a prime (1664557) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10131 + ... + 10293.

It is an arithmetic number, because the mean of its divisors is an integer number (87248).

2^1664556 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 1664556, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2093952).

1664556 is an abundant number, since it is smaller than the sum of its proper divisors (2523348).

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

1664556 is a wasteful number, since it uses less digits than its factorization.

1664556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 230 (or 228 counting only the distinct ones).

The product of its digits is 21600, while the sum is 33.

The square root of 1664556 is about 1290.1767320798. The cubic root of 1664556 is about 118.5130395664.

The spelling of 1664556 in words is "one million, six hundred sixty-four thousand, five hundred fifty-six".