20110209 has 16 divisors (see below), whose sum is σ = 31165440. Its totient is φ = 11296080.

The previous prime is 20110183. The next prime is 20110217. The reversal of 20110209 is 90201102.

It is a happy number.

It is not a de Polignac number, because 20110209 - 2⁸ = 20109953 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20110229) 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, 6877 + ... + 9354.

It is an arithmetic number, because the mean of its divisors is an integer number (1947840).

Almost surely, 2^20110209 is an apocalyptic number.

It is an amenable number.

20110209 is a deficient number, since it is larger than the sum of its proper divisors (11055231).

20110209 is a wasteful number, since it uses less digits than its factorization.

20110209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16300.

The product of its (nonzero) digits is 36, while the sum is 15.

The square root of 20110209 is about 4484.4407678104. The cubic root of 20110209 is about 271.9394373886.

The spelling of 20110209 in words is "twenty million, one hundred ten thousand, two hundred nine".