20408459 has 2 divisors, whose sum is σ = 20408460. Its totient is φ = 20408458.

The previous prime is 20408419. The next prime is 20408461. The reversal of 20408459 is 95480402.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20408459 - 2¹⁶ = 20342923 is a prime.

Together with 20408461, it forms a pair of twin primes.

It is a Chen prime.

It is equal to p_1294844 and since 20408459 and 1294844 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (20408419) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10204229 + 10204230.

It is an arithmetic number, because the mean of its divisors is an integer number (10204230).

Almost surely, 2^20408459 is an apocalyptic number.

20408459 is a deficient number, since it is larger than the sum of its proper divisors (1).

20408459 is an equidigital number, since it uses as much as digits as its factorization.

20408459 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11520, while the sum is 32.

The square root of 20408459 is about 4517.5722462402. The cubic root of 20408459 is about 273.2772032604.

The spelling of 20408459 in words is "twenty million, four hundred eight thousand, four hundred fifty-nine".