20091011 has 4 divisors (see below), whose sum is σ = 20226000. Its totient is φ = 19956024.

The previous prime is 20090977. The next prime is 20091023. The reversal of 20091011 is 11019002.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20091011 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20091311) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 67271 + ... + 67568.

It is an arithmetic number, because the mean of its divisors is an integer number (5056500).

Almost surely, 2^20091011 is an apocalyptic number.

20091011 is a deficient number, since it is larger than the sum of its proper divisors (134989).

20091011 is a wasteful number, since it uses less digits than its factorization.

20091011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 134988.

The product of its (nonzero) digits is 18, while the sum is 14.

The square root of 20091011 is about 4482.2997445508. The cubic root of 20091011 is about 271.8528751274.

The spelling of 20091011 in words is "twenty million, ninety-one thousand, eleven".