20655217 has 8 divisors (see below), whose sum is σ = 22632480. Its totient is φ = 18694560.

The previous prime is 20655203. The next prime is 20655227. The reversal of 20655217 is 71255602.

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 20655217 - 2¹¹ = 20653169 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20655227) 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 7 ways as a sum of consecutive naturals, for example, 1467 + ... + 6592.

It is an arithmetic number, because the mean of its divisors is an integer number (2829060).

Almost surely, 2^20655217 is an apocalyptic number.

It is an amenable number.

20655217 is a deficient number, since it is larger than the sum of its proper divisors (1977263).

20655217 is a wasteful number, since it uses less digits than its factorization.

20655217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8303.

The product of its (nonzero) digits is 4200, while the sum is 28.

The square root of 20655217 is about 4544.8010957577. The cubic root of 20655217 is about 274.3741890585.

It can be divided in two parts, 2065521 and 7, that added together give a triangular number (2065528 = T₂₀₃₂).

The spelling of 20655217 in words is "twenty million, six hundred fifty-five thousand, two hundred seventeen".