20001020221 has 32 divisors (see below), whose sum is σ = 24766334208. Its totient is φ = 15729085440.

The previous prime is 20001020219. The next prime is 20001020243. The reversal of 20001020221 is 12202010002.

It is a cyclic number.

It is not a de Polignac number, because 20001020221 - 2¹ = 20001020219 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20001020198 and 20001020207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20001020521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 12878181 + ... + 12879733.

It is an arithmetic number, because the mean of its divisors is an integer number (773947944).

Almost surely, 2^20001020221 is an apocalyptic number.

It is an amenable number.

20001020221 is a deficient number, since it is larger than the sum of its proper divisors (4765313987).

20001020221 is a wasteful number, since it uses less digits than its factorization.

20001020221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2341.

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

Adding to 20001020221 its reverse (12202010002), we get a palindrome (32203030223).

The spelling of 20001020221 in words is "twenty billion, one million, twenty thousand, two hundred twenty-one".