20201220221 has 16 divisors (see below), whose sum is σ = 24873698304. Its totient is φ = 15976531584.

The previous prime is 20201220209. The next prime is 20201220239. The reversal of 20201220221 is 12202210202.

It is not a de Polignac number, because 20201220221 - 2⁶ = 20201220157 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20201220196 and 20201220205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20201222221) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 171380 + ... + 264146.

It is an arithmetic number, because the mean of its divisors is an integer number (1554606144).

Almost surely, 2^20201220221 is an apocalyptic number.

It is an amenable number.

20201220221 is a deficient number, since it is larger than the sum of its proper divisors (4672478083).

20201220221 is a wasteful number, since it uses less digits than its factorization.

20201220221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95180.

The product of its (nonzero) digits is 64, while the sum is 14.

Adding to 20201220221 its reverse (12202210202), we get a palindrome (32403430423).

The spelling of 20201220221 in words is "twenty billion, two hundred one million, two hundred twenty thousand, two hundred twenty-one".