1123212440 has 128 divisors (see below), whose sum is σ = 3096092160. Its totient is φ = 357955584.

The previous prime is 1123212407. The next prime is 1123212451. The reversal of 1123212440 is 442123211.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 393659 + ... + 396501.

It is an arithmetic number, because the mean of its divisors is an integer number (24188220).

Almost surely, 2^1123212440 is an apocalyptic number.

1123212440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1123212440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1548046080).

1123212440 is an abundant number, since it is smaller than the sum of its proper divisors (1972879720).

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

1123212440 is a wasteful number, since it uses less digits than its factorization.

1123212440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2961 (or 2957 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 20.

The square root of 1123212440 is about 33514.3616976364. The cubic root of 1123212440 is about 1039.4907640069.

Adding to 1123212440 its reverse (442123211), we get a palindrome (1565335651).

The spelling of 1123212440 in words is "one billion, one hundred twenty-three million, two hundred twelve thousand, four hundred forty".