20207917 has 8 divisors (see below), whose sum is σ = 21474936. Its totient is φ = 18949632.

The previous prime is 20207909. The next prime is 20207953. The reversal of 20207917 is 71970202.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 10850436 + 9357481 = 3294^2 + 3059^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20207917 - 2³ = 20207909 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20207977) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2953 + ... + 7009.

It is an arithmetic number, because the mean of its divisors is an integer number (2684367).

Almost surely, 2^20207917 is an apocalyptic number.

It is an amenable number.

20207917 is a deficient number, since it is larger than the sum of its proper divisors (1267019).

20207917 is a wasteful number, since it uses less digits than its factorization.

20207917 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4367.

The product of its (nonzero) digits is 1764, while the sum is 28.

The square root of 20207917 is about 4495.3216792572. The cubic root of 20207917 is about 272.3791434441.

It can be divided in two parts, 202079 and 17, that multiplied together give a palindrome (3435343).

The spelling of 20207917 in words is "twenty million, two hundred seven thousand, nine hundred seventeen".