221121002000 has 80 divisors (see below), whose sum is σ = 537069292032. Its totient is φ = 88051593600.

The previous prime is 221121001993. The next prime is 221121002009. The reversal of 221121002000 is 200121122.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

It is not an unprimeable number, because it can be changed into a prime (221121002009) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 198107 + ... + 693893.

Almost surely, 2^221121002000 is an apocalyptic number.

221121002000 is a gapful number since it is divisible by the number (20) 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 221121002000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (268534646016).

221121002000 is an abundant number, since it is smaller than the sum of its proper divisors (315948290032).

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

221121002000 is a wasteful number, since it uses less digits than its factorization.

221121002000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 496033 (or 496017 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 221121002000 its reverse (200121122), we get a palindrome (221321123122).

The spelling of 221121002000 in words is "two hundred twenty-one billion, one hundred twenty-one million, two thousand".