221002100020 has 96 divisors (see below), whose sum is σ = 502351920000. Its totient is φ = 81186015744.

The previous prime is 221002099931. The next prime is 221002100051. The reversal of 221002100020 is 20001200122.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a congruent 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, 45017326 + ... + 45022234.

It is an arithmetic number, because the mean of its divisors is an integer number (5232832500).

Almost surely, 2^221002100020 is an apocalyptic number.

221002100020 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 221002100020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (251175960000).

221002100020 is an abundant number, since it is smaller than the sum of its proper divisors (281349819980).

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

221002100020 is a wasteful number, since it uses less digits than its factorization.

221002100020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5777 (or 5775 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 10.

Adding to 221002100020 its reverse (20001200122), we get a palindrome (241003300142).

The spelling of 221002100020 in words is "two hundred twenty-one billion, two million, one hundred thousand, twenty".