20900217 has 16 divisors (see below), whose sum is σ = 30199680. Its totient is φ = 12780672.

The previous prime is 20900189. The next prime is 20900221. The reversal of 20900217 is 71200902.

It is a happy number.

It is not a de Polignac number, because 20900217 - 2⁸ = 20899961 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20900193 and 20900202.

It is not an unprimeable number, because it can be changed into a prime (20900267) 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, 4909 + ... + 8117.

It is an arithmetic number, because the mean of its divisors is an integer number (1887480).

Almost surely, 2^20900217 is an apocalyptic number.

It is an amenable number.

20900217 is a deficient number, since it is larger than the sum of its proper divisors (9299463).

20900217 is a wasteful number, since it uses less digits than its factorization.

20900217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3392.

The product of its (nonzero) digits is 252, while the sum is 21.

The square root of 20900217 is about 4571.6755134196. The cubic root of 20900217 is about 275.4547495243.

The spelling of 20900217 in words is "twenty million, nine hundred thousand, two hundred seventeen".