20091911 has 16 divisors (see below), whose sum is σ = 24672000. Its totient is φ = 16309944.

The previous prime is 20091881. The next prime is 20091913. The reversal of 20091911 is 11919002.

It is not a de Polignac number, because 20091911 - 2⁶ = 20091847 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20091913) 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, 4976 + ... + 8058.

It is an arithmetic number, because the mean of its divisors is an integer number (1542000).

Almost surely, 2^20091911 is an apocalyptic number.

20091911 is a deficient number, since it is larger than the sum of its proper divisors (4580089).

20091911 is an equidigital number, since it uses as much as digits as its factorization.

20091911 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3123 (or 3109 counting only the distinct ones).

The product of its (nonzero) digits is 162, while the sum is 23.

The square root of 20091911 is about 4482.4001383188. The cubic root of 20091911 is about 271.8569343877.

The spelling of 20091911 in words is "twenty million, ninety-one thousand, nine hundred eleven".