1091233920 has 256 divisors, whose sum is σ = 4058784000. Its totient is φ = 249274368.

The previous prime is 1091233889. The next prime is 1091233937. The reversal of 1091233920 is 293321901.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (30).

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, 657732 + ... + 659388.

It is an arithmetic number, because the mean of its divisors is an integer number (15854625).

Almost surely, 2^1091233920 is an apocalyptic number.

1091233920 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 1091233920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2029392000).

1091233920 is an abundant number, since it is smaller than the sum of its proper divisors (2967550080).

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

1091233920 is an equidigital number, since it uses as much as digits as its factorization.

1091233920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1700 (or 1674 counting only the distinct ones).

The product of its (nonzero) digits is 2916, while the sum is 30.

The square root of 1091233920 is about 33033.8299323587. The cubic root of 1091233920 is about 1029.5306624706.

The spelling of 1091233920 in words is "one billion, ninety-one million, two hundred thirty-three thousand, nine hundred twenty".