1091820000 has 240 divisors, whose sum is σ = 3703214592. Its totient is φ = 281280000.

The previous prime is 1091819983. The next prime is 1091820001. The reversal of 1091820000 is 281901.

It is a tau number, because it is divible by the number of its divisors (240).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1091820001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1859707 + ... + 1860293.

Almost surely, 2^1091820000 is an apocalyptic number.

1091820000 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 1091820000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1851607296).

1091820000 is an abundant number, since it is smaller than the sum of its proper divisors (2611394592).

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

1091820000 is an equidigital number, since it uses as much as digits as its factorization.

1091820000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 651 (or 628 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 21.

The square root of 1091820000 is about 33042.6996475772. The cubic root of 1091820000 is about 1029.7149429533.

The spelling of 1091820000 in words is "one billion, ninety-one million, eight hundred twenty thousand".