1218100000 has 144 divisors (see below), whose sum is σ = 3231496296. Its totient is φ = 449280000.

The previous prime is 1218099989. The next prime is 1218100003. The reversal of 1218100000 is 18121.

It can be written as a sum of positive squares in 12 ways, for example, as 1074003984 + 144096016 = 32772^2 + 12004^2 .

It is a super-2 number, since 2×1218100000² = 2967535220000000000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is not an unprimeable number, because it can be changed into a prime (1218100003) 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 23 ways as a sum of consecutive naturals, for example, 1299532 + ... + 1300468.

Almost surely, 2^1218100000 is an apocalyptic number.

1218100000 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 1218100000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1615748148).

1218100000 is an abundant number, since it is smaller than the sum of its proper divisors (2013396296).

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

1218100000 is an frugal number, since it uses more digits than its factorization.

1218100000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 985 (or 957 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

The square root of 1218100000 is about 34901.2893744629. The cubic root of 1218100000 is about 1067.9747407138.

Adding to 1218100000 its reverse (18121), we get a palindrome (1218118121).

The spelling of 1218100000 in words is "one billion, two hundred eighteen million, one hundred thousand".