20459487 has 4 divisors (see below), whose sum is σ = 27279320. Its totient is φ = 13639656.

The previous prime is 20459459. The next prime is 20459503. The reversal of 20459487 is 78495402.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 20459487 - 2¹⁵ = 20426719 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20459987) 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, 3409912 + ... + 3409917.

It is an arithmetic number, because the mean of its divisors is an integer number (6819830).

Almost surely, 2^20459487 is an apocalyptic number.

20459487 is a deficient number, since it is larger than the sum of its proper divisors (6819833).

20459487 is an equidigital number, since it uses as much as digits as its factorization.

20459487 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6819832.

The product of its (nonzero) digits is 80640, while the sum is 39.

The square root of 20459487 is about 4523.2164440805. The cubic root of 20459487 is about 273.5047752855.

The spelling of 20459487 in words is "twenty million, four hundred fifty-nine thousand, four hundred eighty-seven".