221020020000 has 720 divisors, whose sum is σ = 875256422040. Its totient is φ = 52512768000.

The previous prime is 221020019993. The next prime is 221020020007. The reversal of 221020020000 is 20020122.

It is an interprime number because it is at equal distance from previous prime (221020019993) and next prime (221020020007).

It can be written as a sum of positive squares in 20 ways, for example, as 83269182096 + 137750837904 = 288564^2 + 371148^2 .

It is a tau number, because it is divible by the number of its divisors (720).

It is a Harshad number since it is a multiple of its sum of digits (9).

It is not an unprimeable number, because it can be changed into a prime (221020020007) by changing a digit.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 67858372 + ... + 67861628.

Almost surely, 2^221020020000 is an apocalyptic number.

221020020000 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 221020020000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (437628211020).

221020020000 is an abundant number, since it is smaller than the sum of its proper divisors (654236402040).

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

221020020000 is a wasteful number, since it uses less digits than its factorization.

221020020000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3335 (or 3309 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 9.

Adding to 221020020000 its reverse (20020122), we get a palindrome (221040040122).

The spelling of 221020020000 in words is "two hundred twenty-one billion, twenty million, twenty thousand".