20501305 has 8 divisors (see below), whose sum is σ = 26838144. Its totient is φ = 14910000.

The previous prime is 20501291. The next prime is 20501309. The reversal of 20501305 is 50310502.

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

It is not a de Polignac number, because 20501305 - 2¹³ = 20493113 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20501309) 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 in 7 ways as a sum of consecutive naturals, for example, 186321 + ... + 186430.

It is an arithmetic number, because the mean of its divisors is an integer number (3354768).

Almost surely, 2^20501305 is an apocalyptic number.

It is an amenable number.

20501305 is a deficient number, since it is larger than the sum of its proper divisors (6336839).

20501305 is a wasteful number, since it uses less digits than its factorization.

20501305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 372767.

The product of its (nonzero) digits is 150, while the sum is 16.

The square root of 20501305 is about 4527.8366799168. The cubic root of 20501305 is about 273.6909910828.

Adding to 20501305 its reverse (50310502), we get a palindrome (70811807).

The spelling of 20501305 in words is "twenty million, five hundred one thousand, three hundred five".