1121312100 has 144 divisors (see below), whose sum is σ = 3421031040. Its totient is φ = 283008000.

The previous prime is 1121312089. The next prime is 1121312107. The reversal of 1121312100 is 12131211.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is not an unprimeable number, because it can be changed into a prime (1121312107) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 696096 + ... + 697704.

It is an arithmetic number, because the mean of its divisors is an integer number (23757160).

Almost surely, 2^1121312100 is an apocalyptic number.

1121312100 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 1121312100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1710515520).

1121312100 is an abundant number, since it is smaller than the sum of its proper divisors (2299718940).

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

1121312100 is a wasteful number, since it uses less digits than its factorization.

1121312100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1750 (or 1743 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 12.

The square root of 1121312100 is about 33485.9985665651. The cubic root of 1121312100 is about 1038.9042020783.

Adding to 1121312100 its reverse (12131211), we get a palindrome (1133443311).

The spelling of 1121312100 in words is "one billion, one hundred twenty-one million, three hundred twelve thousand, one hundred".