20200218221 has 4 divisors (see below), whose sum is σ = 20896777500. Its totient is φ = 19503658944.

The previous prime is 20200218217. The next prime is 20200218251. The reversal of 20200218221 is 12281200202.

It is a happy number.

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 4507645321 + 15692572900 = 67139^2 + 125270^2 .

It is a cyclic number.

It is not a de Polignac number, because 20200218221 - 2² = 20200218217 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 20200218193 and 20200218202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20200218251) 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, 348279596 + ... + 348279653.

It is an arithmetic number, because the mean of its divisors is an integer number (5224194375).

Almost surely, 2^20200218221 is an apocalyptic number.

It is an amenable number.

20200218221 is a deficient number, since it is larger than the sum of its proper divisors (696559279).

20200218221 is an equidigital number, since it uses as much as digits as its factorization.

20200218221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 696559278.

The product of its (nonzero) digits is 256, while the sum is 20.

Adding to 20200218221 its reverse (12281200202), we get a palindrome (32481418423).

The spelling of 20200218221 in words is "twenty billion, two hundred million, two hundred eighteen thousand, two hundred twenty-one".