20650517 has 4 divisors (see below), whose sum is σ = 20663916. Its totient is φ = 20637120.

The previous prime is 20650507. The next prime is 20650519. The reversal of 20650517 is 71505602.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 5354596 + 15295921 = 2314^2 + 3911^2 .

It is a cyclic number.

It is not a de Polignac number, because 20650517 - 2⁴ = 20650501 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 (20650519) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4034 + ... + 7587.

It is an arithmetic number, because the mean of its divisors is an integer number (5165979).

Almost surely, 2^20650517 is an apocalyptic number.

It is an amenable number.

20650517 is a deficient number, since it is larger than the sum of its proper divisors (13399).

20650517 is a wasteful number, since it uses less digits than its factorization.

20650517 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13398.

The product of its (nonzero) digits is 2100, while the sum is 26.

The square root of 20650517 is about 4544.2839920058. The cubic root of 20650517 is about 274.3533766166.

The spelling of 20650517 in words is "twenty million, six hundred fifty thousand, five hundred seventeen".