20091611 has 4 divisors (see below), whose sum is σ = 20470752. Its totient is φ = 19712472.

The previous prime is 20091587. The next prime is 20091613. The reversal of 20091611 is 11619002.

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

It is a cyclic number.

It is not a de Polignac number, because 20091611 - 2¹⁴ = 20075227 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20091613) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 189491 + ... + 189596.

It is an arithmetic number, because the mean of its divisors is an integer number (5117688).

Almost surely, 2^20091611 is an apocalyptic number.

20091611 is a deficient number, since it is larger than the sum of its proper divisors (379141).

20091611 is an equidigital number, since it uses as much as digits as its factorization.

20091611 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 379140.

The product of its (nonzero) digits is 108, while the sum is 20.

The square root of 20091611 is about 4482.3666739793. The cubic root of 20091611 is about 271.8555813144.

It can be divided in two parts, 20091 and 611, that added together give a palindrome (20702).

The spelling of 20091611 in words is "twenty million, ninety-one thousand, six hundred eleven".