20535217 has 2 divisors, whose sum is σ = 20535218. Its totient is φ = 20535216.

The previous prime is 20535211. The next prime is 20535227. The reversal of 20535217 is 71253502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17631601 + 2903616 = 4199^2 + 1704^2 .

It is a cyclic number.

It is not a de Polignac number, because 20535217 - 2⁷ = 20535089 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20535191 and 20535200.

It is not a weakly prime, because it can be changed into another prime (20535211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10267608 + 10267609.

It is an arithmetic number, because the mean of its divisors is an integer number (10267609).

Almost surely, 2^20535217 is an apocalyptic number.

It is an amenable number.

20535217 is a deficient number, since it is larger than the sum of its proper divisors (1).

20535217 is an equidigital number, since it uses as much as digits as its factorization.

20535217 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2100, while the sum is 25.

The square root of 20535217 is about 4531.5799672962. The cubic root of 20535217 is about 273.8418155630.

Adding to 20535217 its reverse (71253502), we get a palindrome (91788719).

The spelling of 20535217 in words is "twenty million, five hundred thirty-five thousand, two hundred seventeen".