20404404222121 has 4 divisors (see below), whose sum is σ = 20463206540112. Its totient is φ = 20345601904132.

The previous prime is 20404404222061. The next prime is 20404404222161. The reversal of 20404404222121 is 12122240440402.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20404404222121 - 2¹³ = 20404404213929 is a prime.

It is a super-2 number, since 2×20404404222121² (a number of 27 digits) contains 22 as substring.

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 20404404222121.

It is not an unprimeable number, because it can be changed into a prime (20404404222161) 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, 29401158475 + ... + 29401159168.

It is an arithmetic number, because the mean of its divisors is an integer number (5115801635028).

Almost surely, 2^{20404404222121} is an apocalyptic number.

It is an amenable number.

20404404222121 is a deficient number, since it is larger than the sum of its proper divisors (58802317991).

20404404222121 is an equidigital number, since it uses as much as digits as its factorization.

20404404222121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58802317990.

The product of its (nonzero) digits is 8192, while the sum is 28.

Adding to 20404404222121 its reverse (12122240440402), we get a palindrome (32526644662523).

The spelling of 20404404222121 in words is "twenty trillion, four hundred four billion, four hundred four million, two hundred twenty-two thousand, one hundred twenty-one".