1147989 has 4 divisors (see below), whose sum is σ = 1530656. Its totient is φ = 765324.

The previous prime is 1147987. The next prime is 1147997. The reversal of 1147989 is 9897411.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 9897411 = 3 ⋅3299137.

It is not a de Polignac number, because 1147989 - 2¹ = 1147987 is a prime.

It is an Ulam number.

It is a D-number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1147981) 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, 191329 + ... + 191334.

It is an arithmetic number, because the mean of its divisors is an integer number (382664).

2^1147989 is an apocalyptic number.

It is an amenable number.

1147989 is a deficient number, since it is larger than the sum of its proper divisors (382667).

1147989 is an equidigital number, since it uses as much as digits as its factorization.

1147989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 382666.

The product of its digits is 18144, while the sum is 39.

The square root of 1147989 is about 1071.4424856239. The cubic root of 1147989 is about 104.7078500129.

The spelling of 1147989 in words is "one million, one hundred forty-seven thousand, nine hundred eighty-nine".