3665638 has 4 divisors (see below), whose sum is σ = 5498460. Its totient is φ = 1832818.

The previous prime is 3665633. The next prime is 3665653. The reversal of 3665638 is 8365663.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 8365663 = 37 ⋅226099.

It is a junction number, because it is equal to n+sod(n) for n = 3665597 and 3665606.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3665633) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 916408 + ... + 916411.

It is an arithmetic number, because the mean of its divisors is an integer number (1374615).

Almost surely, 2^3665638 is an apocalyptic number.

3665638 is a deficient number, since it is larger than the sum of its proper divisors (1832822).

3665638 is a wasteful number, since it uses less digits than its factorization.

3665638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1832821.

The product of its digits is 77760, while the sum is 37.

The square root of 3665638 is about 1914.5855948481. The cubic root of 3665638 is about 154.1877453850.

The spelling of 3665638 in words is "three million, six hundred sixty-five thousand, six hundred thirty-eight".