20443691 has 2 divisors, whose sum is σ = 20443692. Its totient is φ = 20443690.

The previous prime is 20443681. The next prime is 20443693. The reversal of 20443691 is 19634402.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20443691 - 2⁶ = 20443627 is a prime.

It is a Sophie Germain prime.

Together with 20443693, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20443693) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10221845 + 10221846.

It is an arithmetic number, because the mean of its divisors is an integer number (10221846).

Almost surely, 2^20443691 is an apocalyptic number.

20443691 is a deficient number, since it is larger than the sum of its proper divisors (1).

20443691 is an equidigital number, since it uses as much as digits as its factorization.

20443691 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5184, while the sum is 29.

The square root of 20443691 is about 4521.4700043238. The cubic root of 20443691 is about 273.4343695816.

The spelling of 20443691 in words is "twenty million, four hundred forty-three thousand, six hundred ninety-one".