20817107 has 2 divisors, whose sum is σ = 20817108. Its totient is φ = 20817106.

The previous prime is 20817091. The next prime is 20817109. The reversal of 20817107 is 70171802.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20817107 - 2⁴ = 20817091 is a prime.

Together with 20817109, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20817109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10408553 + 10408554.

It is an arithmetic number, because the mean of its divisors is an integer number (10408554).

Almost surely, 2^20817107 is an apocalyptic number.

20817107 is a deficient number, since it is larger than the sum of its proper divisors (1).

20817107 is an equidigital number, since it uses as much as digits as its factorization.

20817107 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 26.

The square root of 20817107 is about 4562.5767938743. The cubic root of 20817107 is about 275.0891479569.

Adding to 20817107 its reverse (70171802), we get a palindrome (90988909).

The spelling of 20817107 in words is "twenty million, eight hundred seventeen thousand, one hundred seven".