20654917 has 4 divisors (see below), whose sum is σ = 21213196. Its totient is φ = 20096640.

The previous prime is 20654903. The next prime is 20654923. The reversal of 20654917 is 71945602.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 71945602 = 2 ⋅35972801.

It can be written as a sum of positive squares in 2 ways, for example, as 9054081 + 11600836 = 3009^2 + 3406^2 .

It is a cyclic number.

It is not a de Polignac number, because 20654917 - 2¹⁵ = 20622149 is a prime.

It is a super-4 number, since 4×20654917⁴ (a number of 30 digits) contains 4444 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20654927) 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 3 ways as a sum of consecutive naturals, for example, 279084 + ... + 279157.

It is an arithmetic number, because the mean of its divisors is an integer number (5303299).

Almost surely, 2^20654917 is an apocalyptic number.

It is an amenable number.

20654917 is a deficient number, since it is larger than the sum of its proper divisors (558279).

20654917 is an equidigital number, since it uses as much as digits as its factorization.

20654917 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 558278.

The product of its (nonzero) digits is 15120, while the sum is 34.

The square root of 20654917 is about 4544.7680908931. The cubic root of 20654917 is about 274.3728606991.

The spelling of 20654917 in words is "twenty million, six hundred fifty-four thousand, nine hundred seventeen".