20001305 has 4 divisors (see below), whose sum is σ = 24001572. Its totient is φ = 16001040.

The previous prime is 20001301. The next prime is 20001307. The reversal of 20001305 is 50310002.

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

It can be written as a sum of positive squares in 2 ways, for example, as 11316496 + 8684809 = 3364^2 + 2947^2 .

It is not a de Polignac number, because 20001305 - 2² = 20001301 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20001301) 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, 2000126 + ... + 2000135.

It is an arithmetic number, because the mean of its divisors is an integer number (6000393).

Almost surely, 2^20001305 is an apocalyptic number.

It is an amenable number.

20001305 is a deficient number, since it is larger than the sum of its proper divisors (4000267).

20001305 is an equidigital number, since it uses as much as digits as its factorization.

20001305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4000266.

The product of its (nonzero) digits is 30, while the sum is 11.

The square root of 20001305 is about 4472.2818560551. The cubic root of 20001305 is about 271.4476653894.

Adding to 20001305 its reverse (50310002), we get a palindrome (70311307).

The spelling of 20001305 in words is "twenty million, one thousand, three hundred five".