20540417 has 2 divisors, whose sum is σ = 20540418. Its totient is φ = 20540416.

The previous prime is 20540413. The next prime is 20540419. The reversal of 20540417 is 71404502.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14508481 + 6031936 = 3809^2 + 2456^2 .

It is a cyclic number.

It is not a de Polignac number, because 20540417 - 2² = 20540413 is a prime.

Together with 20540419, it forms a pair of twin primes.

It is a Chen prime.

It is equal to p_1302647 and since 20540417 and 1302647 have the same sum of digits, it is a Honaker prime.

It is a junction number, because it is equal to n+sod(n) for n = 20540392 and 20540401.

It is not a weakly prime, because it can be changed into another prime (20540413) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10270208 + 10270209.

It is an arithmetic number, because the mean of its divisors is an integer number (10270209).

Almost surely, 2^20540417 is an apocalyptic number.

It is an amenable number.

20540417 is a deficient number, since it is larger than the sum of its proper divisors (1).

20540417 is an equidigital number, since it uses as much as digits as its factorization.

20540417 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1120, while the sum is 23.

The square root of 20540417 is about 4532.1536823016. The cubic root of 20540417 is about 273.8649280087.

Adding to 20540417 its reverse (71404502), we get a palindrome (91944919).

The spelling of 20540417 in words is "twenty million, five hundred forty thousand, four hundred seventeen".