1000221121188 has 36 divisors (see below), whose sum is σ = 2528903639808. Its totient is φ = 333332282160.

The previous prime is 1000221121187. The next prime is 1000221121189. The reversal of 1000221121188 is 8811211220001.

It is an interprime number because it is at equal distance from previous prime (1000221121187) and next prime (1000221121189).

It is a tau number, because it is divible by the number of its divisors (36).

It is not an unprimeable number, because it can be changed into a prime (1000221121187) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2952028 + ... + 3273363.

It is an arithmetic number, because the mean of its divisors is an integer number (70247323328).

Almost surely, 2^{1000221121188} is an apocalyptic number.

1000221121188 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

1000221121188 is an abundant number, since it is smaller than the sum of its proper divisors (1528682518620).

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

1000221121188 is a wasteful number, since it uses less digits than its factorization.

1000221121188 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6229864 (or 6229859 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 27.

Adding to 1000221121188 its reverse (8811211220001), we get a palindrome (9811432341189).

The spelling of 1000221121188 in words is "one trillion, two hundred twenty-one million, one hundred twenty-one thousand, one hundred eighty-eight".