20305061 has 6 divisors (see below), whose sum is σ = 23620230. Its totient is φ = 17404296.

The previous prime is 20305049. The next prime is 20305063. The reversal of 20305061 is 16050302.

It can be written as a sum of positive squares in only one way, i.e., 14025025 + 6280036 = 3745^2 + 2506^2 .

It is not a de Polignac number, because 20305061 - 2⁶ = 20304997 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 (20305063) 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 5 ways as a sum of consecutive naturals, for example, 207146 + ... + 207243.

It is an arithmetic number, because the mean of its divisors is an integer number (3936705).

Almost surely, 2^20305061 is an apocalyptic number.

It is an amenable number.

20305061 is a deficient number, since it is larger than the sum of its proper divisors (3315169).

20305061 is an equidigital number, since it uses as much as digits as its factorization.

20305061 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 414403 (or 414396 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 17.

The square root of 20305061 is about 4506.1137358038. The cubic root of 20305061 is about 272.8149085069.

Adding to 20305061 its reverse (16050302), we get a palindrome (36355363).

The spelling of 20305061 in words is "twenty million, three hundred five thousand, sixty-one".