3643655 has 4 divisors (see below), whose sum is σ = 4372392. Its totient is φ = 2914920.

The previous prime is 3643639. The next prime is 3643657. The reversal of 3643655 is 5563463.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5563463 = 53 ⋅104971.

It is not a de Polignac number, because 3643655 - 2⁴ = 3643639 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3643657) 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, 364361 + ... + 364370.

It is an arithmetic number, because the mean of its divisors is an integer number (1093098).

Almost surely, 2^3643655 is an apocalyptic number.

3643655 is a deficient number, since it is larger than the sum of its proper divisors (728737).

3643655 is an equidigital number, since it uses as much as digits as its factorization.

3643655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 728736.

The product of its digits is 32400, while the sum is 32.

The square root of 3643655 is about 1908.8360327697. The cubic root of 3643655 is about 153.8789035088.

The spelling of 3643655 in words is "three million, six hundred forty-three thousand, six hundred fifty-five".