221221201000 has 128 divisors (see below), whose sum is σ = 520562764800. Its totient is φ = 87993484800.

The previous prime is 221221200997. The next prime is 221221201039. The reversal of 221221201000 is 102122122.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 225046509 + ... + 225047491.

It is an arithmetic number, because the mean of its divisors is an integer number (4066896600).

Almost surely, 2^221221201000 is an apocalyptic number.

221221201000 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 221221201000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (260281382400).

221221201000 is an abundant number, since it is smaller than the sum of its proper divisors (299341563800).

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

221221201000 is a wasteful number, since it uses less digits than its factorization.

221221201000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2036 (or 2022 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 221221201000 its reverse (102122122), we get a palindrome (221323323122).

The spelling of 221221201000 in words is "two hundred twenty-one billion, two hundred twenty-one million, two hundred one thousand".