1003643 has 4 divisors (see below), whose sum is σ = 1005648. Its totient is φ = 1001640.

The previous prime is 1003631. The next prime is 1003679. The reversal of 1003643 is 3463001.

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

It is a cyclic number.

It is not a de Polignac number, because 1003643 - 2⁴ = 1003627 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1003693) 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, 473 + ... + 1493.

It is an arithmetic number, because the mean of its divisors is an integer number (251412).

2^1003643 is an apocalyptic number.

1003643 is a deficient number, since it is larger than the sum of its proper divisors (2005).

1003643 is an equidigital number, since it uses as much as digits as its factorization.

1003643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2004.

The product of its (nonzero) digits is 216, while the sum is 17.

The square root of 1003643 is about 1001.8198440838. The cubic root of 1003643 is about 100.1212861705.

Adding to 1003643 its reverse (3463001), we get a palindrome (4466644).

The spelling of 1003643 in words is "one million, three thousand, six hundred forty-three".