1123456789 has 16 divisors (see below), whose sum is σ = 1420091008.
Its totient is φ = 864862272.
The previous prime is 1123456769. The next prime is 1123456793. The reversal of 1123456789 is 9876543211.
It is not a de Polignac number, because 1123456789 - 29 = 1123456277 is a prime.
It is a deceptive number, since it divides R1123456788.
It is the 80-th primeval number, because it sets a new record (362451) in the number of distinct primes that is it possible to write using its digits.
It is a plaindrome in base 10.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (1123456729) by changing a digit.
It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 163467 + ... + 170200.
It is an arithmetic number, because the mean of its divisors is an integer number (88755688).
Almost surely, 21123456789 is an apocalyptic number.
It is an amenable number.
1123456789 is a deficient number, since it is larger than the sum of its proper divisors (296634219).
1123456789 is a wasteful number, since it uses less digits than its factorization.
1123456789 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 333724.
The product of its digits is 362880, while the sum is 46.
The square root of 1123456789 is about 33518.0069365707.
The cubic root of 1123456789 is about 1039.5661371370.
The spelling of 1123456789 in words is "one billion, one hundred twenty-three million, four hundred fifty-six thousand, seven hundred eighty-nine".