1328665 has 8 divisors (see below), whose sum is σ = 1717128. Its totient is φ = 981120.

The previous prime is 1328653. The next prime is 1328671. The reversal of 1328665 is 5668231.

It can be written as a sum of positive squares in 4 ways, for example, as 127449 + 1201216 = 357^2 + 1096^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-1328665 is a prime.

It is a d-powerful number, because it can be written as 1 + 3³ + 2²⁰ + 8² + 6² + 6⁷ + 5² .

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10156 + ... + 10285.

It is an arithmetic number, because the mean of its divisors is an integer number (214641).

2^1328665 is an apocalyptic number.

It is an amenable number.

1328665 is a deficient number, since it is larger than the sum of its proper divisors (388463).

1328665 is a wasteful number, since it uses less digits than its factorization.

1328665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20459.

The product of its digits is 8640, while the sum is 31.

The square root of 1328665 is about 1152.6773182465. The cubic root of 1328665 is about 109.9356372788.

The spelling of 1328665 in words is "one million, three hundred twenty-eight thousand, six hundred sixty-five".