1123200720 has 90 divisors (see below), whose sum is σ = 3775104918. Its totient is φ = 299280384.

The previous prime is 1123200709. The next prime is 1123200763. The reversal of 1123200720 is 270023211.

It can be written as a sum of positive squares in 3 ways, for example, as 58614336 + 1064586384 = 7656^2 + 32628^2 .

It is a tau number, because it is divible by the number of its divisors (90).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 1123200693 and 1123200702.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 898656 + ... + 899904.

Almost surely, 2^1123200720 is an apocalyptic number.

1123200720 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 1123200720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1887552459).

1123200720 is an abundant number, since it is smaller than the sum of its proper divisors (2651904198).

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

1123200720 is an equidigital number, since it uses as much as digits as its factorization.

1123200720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2517 (or 1259 counting only the distinct ones).

The product of its (nonzero) digits is 168, while the sum is 18.

The square root of 1123200720 is about 33514.1868467668. The cubic root of 1123200720 is about 1039.4871485216.

Adding to 1123200720 its reverse (270023211), we get a palindrome (1393223931).

The spelling of 1123200720 in words is "one billion, one hundred twenty-three million, two hundred thousand, seven hundred twenty".