3645861 has 8 divisors (see below), whose sum is σ = 4898784. Its totient is φ = 2411760.

The previous prime is 3645823. The next prime is 3645877. The reversal of 3645861 is 1685463.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 3645861 - 2⁹ = 3645349 is a prime.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3641861) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4246 + ... + 5031.

It is an arithmetic number, because the mean of its divisors is an integer number (612348).

Almost surely, 2^3645861 is an apocalyptic number.

It is an amenable number.

3645861 is a deficient number, since it is larger than the sum of its proper divisors (1252923).

3645861 is a wasteful number, since it uses less digits than its factorization.

3645861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9411.

The product of its digits is 17280, while the sum is 33.

The square root of 3645861 is about 1909.4137843851. The cubic root of 3645861 is about 153.9099518542.

The spelling of 3645861 in words is "three million, six hundred forty-five thousand, eight hundred sixty-one".