20404331 has 2 divisors, whose sum is σ = 20404332. Its totient is φ = 20404330.

The previous prime is 20404261. The next prime is 20404337. The reversal of 20404331 is 13340402.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20404331 - 2¹⁰ = 20403307 is a prime.

It is a super-2 number, since 2×20404331² = 832673447115122, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20404337) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10202165 + 10202166.

It is an arithmetic number, because the mean of its divisors is an integer number (10202166).

Almost surely, 2^20404331 is an apocalyptic number.

20404331 is a deficient number, since it is larger than the sum of its proper divisors (1).

20404331 is an equidigital number, since it uses as much as digits as its factorization.

20404331 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 288, while the sum is 17.

The square root of 20404331 is about 4517.1153405686. The cubic root of 20404331 is about 273.2587768429.

Adding to 20404331 its reverse (13340402), we get a palindrome (33744733).

The spelling of 20404331 in words is "twenty million, four hundred four thousand, three hundred thirty-one".