1123209018 has 40 divisors (see below), whose sum is σ = 2518987680. Its totient is φ = 374080680.

The previous prime is 1123209013. The next prime is 1123209029. The reversal of 1123209018 is 8109023211.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 1123208982 and 1123209000.

It is not an unprimeable number, because it can be changed into a prime (1123209011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 253603 + ... + 257993.

It is an arithmetic number, because the mean of its divisors is an integer number (62974692).

Almost surely, 2^1123209018 is an apocalyptic number.

1123209018 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

1123209018 is an abundant number, since it is smaller than the sum of its proper divisors (1395778662).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1123209018 is a wasteful number, since it uses less digits than its factorization.

1123209018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5984 (or 5975 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 27.

The square root of 1123209018 is about 33514.3106448574. The cubic root of 1123209018 is about 1039.4897083618.

The spelling of 1123209018 in words is "one billion, one hundred twenty-three million, two hundred nine thousand, eighteen".