1648665 has 12 divisors (see below), whose sum is σ = 2857764. Its totient is φ = 879264.

The previous prime is 1648613. The next prime is 1648697. The reversal of 1648665 is 5668461.

1648665 is a `hidden beast` number, since 1 + 648 + 6 + 6 + 5 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 589824 + 1058841 = 768^2 + 1029^2 .

It is not a de Polignac number, because 1648665 - 2⁶ = 1648601 is a prime.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 18274 + ... + 18363.

It is an arithmetic number, because the mean of its divisors is an integer number (238147).

2^1648665 is an apocalyptic number.

1648665 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1648665 is a deficient number, since it is larger than the sum of its proper divisors (1209099).

1648665 is a wasteful number, since it uses less digits than its factorization.

1648665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36648 (or 36645 counting only the distinct ones).

The product of its digits is 34560, while the sum is 36.

The square root of 1648665 is about 1284.0035046681. The cubic root of 1648665 is about 118.1346972807.

The spelling of 1648665 in words is "one million, six hundred forty-eight thousand, six hundred sixty-five".