20010000221 has 4 divisors (see below), whose sum is σ = 20026177692. Its totient is φ = 19993822752.

The previous prime is 20010000191. The next prime is 20010000247. The reversal of 20010000221 is 12200001002.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 17918767321 + 2091232900 = 133861^2 + 45730^2 .

It is a cyclic number.

It is not a de Polignac number, because 20010000221 - 2²² = 20005805917 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20010000199 and 20010000208.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20010000281) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8086880 + ... + 8089353.

It is an arithmetic number, because the mean of its divisors is an integer number (5006544423).

Almost surely, 2^20010000221 is an apocalyptic number.

It is an amenable number.

20010000221 is a deficient number, since it is larger than the sum of its proper divisors (16177471).

20010000221 is a wasteful number, since it uses less digits than its factorization.

20010000221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16177470.

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

Adding to 20010000221 its reverse (12200001002), we get a palindrome (32210001223).

The spelling of 20010000221 in words is "twenty billion, ten million, two hundred twenty-one", and thus it is an aban number.