1606644 has 36 divisors (see below), whose sum is σ = 4374916. Its totient is φ = 494208.

The previous prime is 1606643. The next prime is 1606663. The reversal of 1606644 is 4466061.

1606644 is a `hidden beast` number, since 16 + 0 + 6 + 644 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 374544 + 1232100 = 612^2 + 1110^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a Smith number, since the sum of its digits (27) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1606643) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1249 + ... + 2184.

2^1606644 is an apocalyptic number.

It is an amenable number.

1606644 is an abundant number, since it is smaller than the sum of its proper divisors (2768272).

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

1606644 is a wasteful number, since it uses less digits than its factorization.

1606644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3456 (or 3451 counting only the distinct ones).

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

The square root of 1606644 is about 1267.5346149120. The cubic root of 1606644 is about 117.1223790724.

It can be divided in two parts, 16066 and 44, that added together give a triangular number (16110 = T₁₇₉).

The spelling of 1606644 in words is "one million, six hundred six thousand, six hundred forty-four".