20804217 has 16 divisors (see below), whose sum is σ = 32440320. Its totient is φ = 11611152.

The previous prime is 20804159. The next prime is 20804257. The reversal of 20804217 is 71240802.

It is not a de Polignac number, because 20804217 - 2⁸ = 20803961 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20804257) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10617 + ... + 12422.

It is an arithmetic number, because the mean of its divisors is an integer number (2027520).

Almost surely, 2^20804217 is an apocalyptic number.

It is an amenable number.

20804217 is a deficient number, since it is larger than the sum of its proper divisors (11636103).

20804217 is a wasteful number, since it uses less digits than its factorization.

20804217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23092.

The product of its (nonzero) digits is 896, while the sum is 24.

The square root of 20804217 is about 4561.1639961747. The cubic root of 20804217 is about 275.0323576250.

The spelling of 20804217 in words is "twenty million, eight hundred four thousand, two hundred seventeen".