3665857 has 4 divisors (see below), whose sum is σ = 3947860. Its totient is φ = 3383856.

The previous prime is 3665839. The next prime is 3665869. The reversal of 3665857 is 7585663.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7585663 = 307 ⋅24709.

It can be written as a sum of positive squares in 2 ways, for example, as 2322576 + 1343281 = 1524^2 + 1159^2 .

It is a cyclic number.

It is not a de Polignac number, because 3665857 - 2¹⁹ = 3141569 is a prime.

It is a super-3 number, since 3×3665857³ (a number of 21 digits) contains 333 as substring.

It is a Duffinian number.

3665857 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (3665807) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 140982 + ... + 141007.

It is an arithmetic number, because the mean of its divisors is an integer number (986965).

Almost surely, 2^3665857 is an apocalyptic number.

It is an amenable number.

3665857 is a deficient number, since it is larger than the sum of its proper divisors (282003).

3665857 is a wasteful number, since it uses less digits than its factorization.

3665857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 282002.

The product of its digits is 151200, while the sum is 40.

The square root of 3665857 is about 1914.6427865270. The cubic root of 3665857 is about 154.1908159232.

The spelling of 3665857 in words is "three million, six hundred sixty-five thousand, eight hundred fifty-seven".