20635169 has 2 divisors, whose sum is σ = 20635170. Its totient is φ = 20635168.

The previous prime is 20635103. The next prime is 20635171. The reversal of 20635169 is 96153602.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19254544 + 1380625 = 4388^2 + 1175^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20635169 is a prime.

It is a super-2 number, since 2×20635169² = 851620399317122, which contains 22 as substring.

Together with 20635171, 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 (20635469) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10317584 + 10317585.

It is an arithmetic number, because the mean of its divisors is an integer number (10317585).

Almost surely, 2^20635169 is an apocalyptic number.

It is an amenable number.

20635169 is a deficient number, since it is larger than the sum of its proper divisors (1).

20635169 is an equidigital number, since it uses as much as digits as its factorization.

20635169 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9720, while the sum is 32.

The square root of 20635169 is about 4542.5949632341. The cubic root of 20635169 is about 274.2853909217.

The spelling of 20635169 in words is "twenty million, six hundred thirty-five thousand, one hundred sixty-nine".