20540305 has 8 divisors (see below), whose sum is σ = 24672744. Its totient is φ = 16416000.

The previous prime is 20540293. The next prime is 20540329. The reversal of 20540305 is 50304502.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 398161 + 20142144 = 631^2 + 4488^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20540305 - 2¹⁵ = 20507537 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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 in 7 ways as a sum of consecutive naturals, for example, 8425 + ... + 10585.

It is an arithmetic number, because the mean of its divisors is an integer number (3084093).

Almost surely, 2^20540305 is an apocalyptic number.

It is an amenable number.

20540305 is a deficient number, since it is larger than the sum of its proper divisors (4132439).

20540305 is a wasteful number, since it uses less digits than its factorization.

20540305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4067.

The product of its (nonzero) digits is 600, while the sum is 19.

The square root of 20540305 is about 4532.1413261283. The cubic root of 20540305 is about 273.8644302432.

Adding to 20540305 its reverse (50304502), we get a palindrome (70844807).

The spelling of 20540305 in words is "twenty million, five hundred forty thousand, three hundred five".