20470217 has 2 divisors, whose sum is σ = 20470218. Its totient is φ = 20470216.

The previous prime is 20470189. The next prime is 20470237. The reversal of 20470217 is 71207402.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13808656 + 6661561 = 3716^2 + 2581^2 .

It is a cyclic number.

It is not a de Polignac number, because 20470217 - 2⁸ = 20469961 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20470192 and 20470201.

It is not a weakly prime, because it can be changed into another prime (20470237) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10235108 + 10235109.

It is an arithmetic number, because the mean of its divisors is an integer number (10235109).

Almost surely, 2^20470217 is an apocalyptic number.

It is an amenable number.

20470217 is a deficient number, since it is larger than the sum of its proper divisors (1).

20470217 is an equidigital number, since it uses as much as digits as its factorization.

20470217 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 784, while the sum is 23.

The square root of 20470217 is about 4524.4023914767. The cubic root of 20470217 is about 273.5525802207.

Adding to 20470217 its reverse (71207402), we get a palindrome (91677619).

The spelling of 20470217 in words is "twenty million, four hundred seventy thousand, two hundred seventeen".