20109081 has 8 divisors (see below), whose sum is σ = 26832960. Its totient is φ = 13395632.

The previous prime is 20109073. The next prime is 20109109. The reversal of 20109081 is 18090102.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20109081 - 2³ = 20109073 is a prime.

It is a super-2 number, since 2×20109081² = 808750277329122, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20109041) 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 7 ways as a sum of consecutive naturals, for example, 5476 + ... + 8378.

It is an arithmetic number, because the mean of its divisors is an integer number (3354120).

Almost surely, 2^20109081 is an apocalyptic number.

It is an amenable number.

20109081 is a deficient number, since it is larger than the sum of its proper divisors (6723879).

20109081 is a wasteful number, since it uses less digits than its factorization.

20109081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5215.

The product of its (nonzero) digits is 144, while the sum is 21.

The square root of 20109081 is about 4484.3149978564. The cubic root of 20109081 is about 271.9343528497.

Adding to 20109081 its reverse (18090102), we get a palindrome (38199183).

The spelling of 20109081 in words is "twenty million, one hundred nine thousand, eighty-one".