1203989 has 4 divisors (see below), whose sum is σ = 1220556. Its totient is φ = 1187424.

The previous prime is 1203971. The next prime is 1204003. The reversal of 1203989 is 9893021.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9893021 = 1979 ⋅4999.

It can be written as a sum of positive squares in 2 ways, for example, as 286225 + 917764 = 535^2 + 958^2 .

It is a cyclic number.

It is not a de Polignac number, because 1203989 - 2⁸ = 1203733 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 (1203919) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8174 + ... + 8319.

It is an arithmetic number, because the mean of its divisors is an integer number (305139).

2^1203989 is an apocalyptic number.

It is an amenable number.

1203989 is a deficient number, since it is larger than the sum of its proper divisors (16567).

1203989 is an equidigital number, since it uses as much as digits as its factorization.

1203989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16566.

The product of its (nonzero) digits is 3888, while the sum is 32.

The square root of 1203989 is about 1097.2643254932. The cubic root of 1203989 is about 106.3834751600.

Adding to 1203989 its sum of digits (32), we get a palindrome (1204021).

The spelling of 1203989 in words is "one million, two hundred three thousand, nine hundred eighty-nine".