20011000221 has 12 divisors (see below), whose sum is σ = 29034398848. Its totient is φ = 13280841864.

The previous prime is 20011000213. The next prime is 20011000223. The reversal of 20011000221 is 12200011002.

It is not a de Polignac number, because 20011000221 - 2³ = 20011000213 is a prime.

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

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20011000223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4983295 + ... + 4987308.

Almost surely, 2^20011000221 is an apocalyptic number.

It is an amenable number.

20011000221 is a deficient number, since it is larger than the sum of its proper divisors (9023398627).

20011000221 is a wasteful number, since it uses less digits than its factorization.

20011000221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9970832 (or 9970829 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

Adding to 20011000221 its reverse (12200011002), we get a palindrome (32211011223).

The spelling of 20011000221 in words is "twenty billion, eleven million, two hundred twenty-one", and thus it is an aban number.