20404011221 has 16 divisors (see below), whose sum is σ = 22362250176. Its totient is φ = 18463200000.

The previous prime is 20404011211. The next prime is 20404011233. The reversal of 20404011221 is 12211040402.

It is a cyclic number.

It is not a de Polignac number, because 20404011221 - 2¹⁴ = 20403994837 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20404011221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20404011211) 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, 2161091 + ... + 2170511.

It is an arithmetic number, because the mean of its divisors is an integer number (1397640636).

Almost surely, 2^20404011221 is an apocalyptic number.

It is an amenable number.

20404011221 is a deficient number, since it is larger than the sum of its proper divisors (1958238955).

20404011221 is a wasteful number, since it uses less digits than its factorization.

20404011221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10324.

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 20404011221 its reverse (12211040402), we get a palindrome (32615051623).

The spelling of 20404011221 in words is "twenty billion, four hundred four million, eleven thousand, two hundred twenty-one".