1123209 has 12 divisors (see below), whose sum is σ = 1666756. Its totient is φ = 728352.

The previous prime is 1123189. The next prime is 1123211. The reversal of 1123209 is 9023211.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 1071225 + 51984 = 1035^2 + 228^2 .

It is not a de Polignac number, because 1123209 - 2⁷ = 1123081 is a prime.

It is a Duffinian number.

1123209 is a lucky number.

It is a plaindrome in base 16.

It is a junction number, because it is equal to n+sod(n) for n = 1123191 and 1123200.

It is not an unprimeable number, because it can be changed into a prime (1123219) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1354 + ... + 2019.

2^1123209 is an apocalyptic number.

It is an amenable number.

1123209 is a deficient number, since it is larger than the sum of its proper divisors (543547).

1123209 is a wasteful number, since it uses less digits than its factorization.

1123209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3416 (or 3413 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

The square root of 1123209 is about 1059.8155499897. The cubic root of 1123209 is about 103.9489702809.

It can be divided in two parts, 112 and 3209, that added together give a triangular number (3321 = T₈₁).

The spelling of 1123209 in words is "one million, one hundred twenty-three thousand, two hundred nine".