20113131091 has 4 divisors (see below), whose sum is σ = 20113524000. Its totient is φ = 20112738184.

The previous prime is 20113131089. The next prime is 20113131107. The reversal of 20113131091 is 19013131102.

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 20113131091 - 2¹ = 20113131089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20113131061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 105691 + ... + 226708.

It is an arithmetic number, because the mean of its divisors is an integer number (5028381000).

Almost surely, 2^20113131091 is an apocalyptic number.

20113131091 is a deficient number, since it is larger than the sum of its proper divisors (392909).

20113131091 is an equidigital number, since it uses as much as digits as its factorization.

20113131091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 392908.

The product of its (nonzero) digits is 162, while the sum is 22.

Adding to 20113131091 its reverse (19013131102), we get a palindrome (39126262193).

The spelling of 20113131091 in words is "twenty billion, one hundred thirteen million, one hundred thirty-one thousand, ninety-one".