1665407 has 16 divisors (see below), whose sum is σ = 1896960. Its totient is φ = 1454112.

The previous prime is 1665343. The next prime is 1665421. The reversal of 1665407 is 7045661.

It is a cyclic number.

It is not a de Polignac number, because 1665407 - 2⁶ = 1665343 is a prime.

It is a Smith number, since the sum of its digits (29) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 1665407.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1665427) 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, 16118 + ... + 16220.

It is an arithmetic number, because the mean of its divisors is an integer number (118560).

2^1665407 is an apocalyptic number.

1665407 is a deficient number, since it is larger than the sum of its proper divisors (231553).

1665407 is a wasteful number, since it uses less digits than its factorization.

1665407 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 182.

The product of its (nonzero) digits is 5040, while the sum is 29.

The square root of 1665407 is about 1290.5064897163. The cubic root of 1665407 is about 118.5332326217.

The spelling of 1665407 in words is "one million, six hundred sixty-five thousand, four hundred seven".