1115720100 has 216 divisors, whose sum is σ = 3838816800. Its totient is φ = 268800000.

The previous prime is 1115720083. The next prime is 1115720107. The reversal of 1115720100 is 10275111.

It is a happy number.

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

It is not an unprimeable number, because it can be changed into a prime (1115720107) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 2484676 + ... + 2485124.

It is an arithmetic number, because the mean of its divisors is an integer number (17772300).

Almost surely, 2^1115720100 is an apocalyptic number.

1115720100 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 1115720100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1919408400).

1115720100 is an abundant number, since it is smaller than the sum of its proper divisors (2723096700).

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

1115720100 is a wasteful number, since it uses less digits than its factorization.

1115720100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 731 (or 721 counting only the distinct ones).

The product of its (nonzero) digits is 70, while the sum is 18.

The square root of 1115720100 is about 33402.3966206019. The cubic root of 1115720100 is about 1037.1743130240.

Adding to 1115720100 its reverse (10275111), we get a palindrome (1125995211).

The spelling of 1115720100 in words is "one billion, one hundred fifteen million, seven hundred twenty thousand, one hundred".