1231603 has 4 divisors (see below), whose sum is σ = 1234240. Its totient is φ = 1228968.

The previous prime is 1231597. The next prime is 1231613. The reversal of 1231603 is 3061321.

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 1231603 - 2⁹ = 1231091 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1231613) 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, 408 + ... + 1621.

It is an arithmetic number, because the mean of its divisors is an integer number (308560).

2^1231603 is an apocalyptic number.

1231603 is a deficient number, since it is larger than the sum of its proper divisors (2637).

1231603 is an equidigital number, since it uses as much as digits as its factorization.

1231603 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2636.

The product of its (nonzero) digits is 108, while the sum is 16.

The square root of 1231603 is about 1109.7761035452. The cubic root of 1231603 is about 107.1906520307.

Adding to 1231603 its reverse (3061321), we get a palindrome (4292924).

The spelling of 1231603 in words is "one million, two hundred thirty-one thousand, six hundred three".