20887423 has 2 divisors, whose sum is σ = 20887424. Its totient is φ = 20887422.

The previous prime is 20887393. The next prime is 20887439. The reversal of 20887423 is 32478802.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20887423 - 2⁹ = 20886911 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20887483) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10443711 + 10443712.

It is an arithmetic number, because the mean of its divisors is an integer number (10443712).

Almost surely, 2^20887423 is an apocalyptic number.

20887423 is a deficient number, since it is larger than the sum of its proper divisors (1).

20887423 is an equidigital number, since it uses as much as digits as its factorization.

20887423 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 21504, while the sum is 34.

The square root of 20887423 is about 4570.2760310511. The cubic root of 20887423 is about 275.3985318080.

The spelling of 20887423 in words is "twenty million, eight hundred eighty-seven thousand, four hundred twenty-three".