20509127 has 2 divisors, whose sum is σ = 20509128. Its totient is φ = 20509126.

The previous prime is 20509117. The next prime is 20509129. The reversal of 20509127 is 72190502.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20509127 - 2¹² = 20505031 is a prime.

Together with 20509129, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 20509096 and 20509105.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20509129) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10254563 + 10254564.

It is an arithmetic number, because the mean of its divisors is an integer number (10254564).

Almost surely, 2^20509127 is an apocalyptic number.

20509127 is a deficient number, since it is larger than the sum of its proper divisors (1).

20509127 is an equidigital number, since it uses as much as digits as its factorization.

20509127 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1260, while the sum is 26.

The square root of 20509127 is about 4528.7003654470. The cubic root of 20509127 is about 273.7257943750.

Adding to 20509127 its reverse (72190502), we get a palindrome (92699629).

The spelling of 20509127 in words is "twenty million, five hundred nine thousand, one hundred twenty-seven".