20185609091 has 8 divisors (see below), whose sum is σ = 20267539200. Its totient is φ = 20103730560.

The previous prime is 20185609079. The next prime is 20185609187. The reversal of 20185609091 is 19090658102.

It is a happy number.

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 20185609091 - 2⁶ = 20185609027 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20185609391) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 901115 + ... + 923243.

It is an arithmetic number, because the mean of its divisors is an integer number (2533442400).

Almost surely, 2^20185609091 is an apocalyptic number.

20185609091 is a deficient number, since it is larger than the sum of its proper divisors (81930109).

20185609091 is a wasteful number, since it uses less digits than its factorization.

20185609091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25789.

The product of its (nonzero) digits is 38880, while the sum is 41.

The spelling of 20185609091 in words is "twenty billion, one hundred eighty-five million, six hundred nine thousand, ninety-one".