1099720800 has 216 divisors, whose sum is σ = 4022226936. Its totient is φ = 293207040.

The previous prime is 1099720793. The next prime is 1099720801. The reversal of 1099720800 is 80279901.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (216).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1099720801) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 191572 + ... + 197228.

It is an arithmetic number, because the mean of its divisors is an integer number (18621421).

Almost surely, 2^1099720800 is an apocalyptic number.

1099720800 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 1099720800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2011113468).

1099720800 is an abundant number, since it is smaller than the sum of its proper divisors (2922506136).

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

1099720800 is an equidigital number, since it uses as much as digits as its factorization.

1099720800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5692 (or 5667 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 36.

The square root of 1099720800 is about 33162.0385380634. The cubic root of 1099720800 is about 1032.1927709121.

The spelling of 1099720800 in words is "one billion, ninety-nine million, seven hundred twenty thousand, eight hundred".