20305121 has 4 divisors (see below), whose sum is σ = 20439744. Its totient is φ = 20170500.

The previous prime is 20305097. The next prime is 20305151. The reversal of 20305121 is 12150302.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20305121 - 2²² = 16110817 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20305096 and 20305105.

It is not an unprimeable number, because it can be changed into a prime (20305151) 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 3 ways as a sum of consecutive naturals, for example, 67085 + ... + 67386.

It is an arithmetic number, because the mean of its divisors is an integer number (5109936).

Almost surely, 2^20305121 is an apocalyptic number.

It is an amenable number.

20305121 is a deficient number, since it is larger than the sum of its proper divisors (134623).

20305121 is a wasteful number, since it uses less digits than its factorization.

20305121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 134622.

The product of its (nonzero) digits is 60, while the sum is 14.

The square root of 20305121 is about 4506.1203934205. The cubic root of 20305121 is about 272.8151772228.

Adding to 20305121 its reverse (12150302), we get a palindrome (32455423).

The spelling of 20305121 in words is "twenty million, three hundred five thousand, one hundred twenty-one".