1609668 has 36 divisors (see below), whose sum is σ = 4141228. Its totient is φ = 527040.

The previous prime is 1609667. The next prime is 1609669. The reversal of 1609668 is 8669061.

It is an interprime number because it is at equal distance from previous prime (1609667) and next prime (1609669).

It can be written as a sum of positive squares in 2 ways, for example, as 831744 + 777924 = 912^2 + 882^2 .

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

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a plaindrome in base 13.

It is a zygodrome in base 13.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1609667) 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, 1830 + ... + 2562.

2^1609668 is an apocalyptic number.

1609668 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1609668, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2070614).

1609668 is an abundant number, since it is smaller than the sum of its proper divisors (2531560).

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

1609668 is a wasteful number, since it uses less digits than its factorization.

1609668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 804 (or 799 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The square root of 1609668 is about 1268.7269209724. The cubic root of 1609668 is about 117.1958149833.

The spelling of 1609668 in words is "one million, six hundred nine thousand, six hundred sixty-eight".