4003645 has 4 divisors (see below), whose sum is σ = 4804380. Its totient is φ = 3202912.

The previous prime is 4003579. The next prime is 4003663. The reversal of 4003645 is 5463004.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1038361 + 2965284 = 1019^2 + 1722^2 .

It is a cyclic number.

It is not a de Polignac number, because 4003645 - 2⁹ = 4003133 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 400360 + ... + 400369.

It is an arithmetic number, because the mean of its divisors is an integer number (1201095).

Almost surely, 2^4003645 is an apocalyptic number.

It is an amenable number.

4003645 is a deficient number, since it is larger than the sum of its proper divisors (800735).

4003645 is an equidigital number, since it uses as much as digits as its factorization.

4003645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 800734.

The product of its (nonzero) digits is 1440, while the sum is 22.

The square root of 4003645 is about 2000.9110425004. The cubic root of 4003645 is about 158.7883078652.

Adding to 4003645 its reverse (5463004), we get a palindrome (9466649).

The spelling of 4003645 in words is "four million, three thousand, six hundred forty-five".