20717253 has 12 divisors (see below), whose sum is σ = 29965260. Its totient is φ = 13792896.

The previous prime is 20717251. The next prime is 20717261. The reversal of 20717253 is 35271702.

It can be written as a sum of positive squares in 2 ways, for example, as 10870209 + 9847044 = 3297^2 + 3138^2 .

It is not a de Polignac number, because 20717253 - 2¹ = 20717251 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20717251) 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 in 11 ways as a sum of consecutive naturals, for example, 10125 + ... + 11997.

It is an arithmetic number, because the mean of its divisors is an integer number (2497105).

Almost surely, 2^20717253 is an apocalyptic number.

It is an amenable number.

20717253 is a deficient number, since it is larger than the sum of its proper divisors (9248007).

20717253 is a wasteful number, since it uses less digits than its factorization.

20717253 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3108 (or 3105 counting only the distinct ones).

The product of its (nonzero) digits is 2940, while the sum is 27.

The square root of 20717253 is about 4551.6209200679. The cubic root of 20717253 is about 274.6486002023.

Adding to 20717253 its reverse (35271702), we get a palindrome (55988955).

The spelling of 20717253 in words is "twenty million, seven hundred seventeen thousand, two hundred fifty-three".