20109427 has 4 divisors (see below), whose sum is σ = 21656320. Its totient is φ = 18562536.

The previous prime is 20109413. The next prime is 20109431. The reversal of 20109427 is 72490102.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20109427 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20109227) 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, 773427 + ... + 773452.

It is an arithmetic number, because the mean of its divisors is an integer number (5414080).

Almost surely, 2^20109427 is an apocalyptic number.

20109427 is a deficient number, since it is larger than the sum of its proper divisors (1546893).

20109427 is a wasteful number, since it uses less digits than its factorization.

20109427 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1546892.

The product of its (nonzero) digits is 1008, while the sum is 25.

The square root of 20109427 is about 4484.3535766039. The cubic root of 20109427 is about 271.9359124891.

Adding to 20109427 its reverse (72490102), we get a palindrome (92599529).

The spelling of 20109427 in words is "twenty million, one hundred nine thousand, four hundred twenty-seven".