20321871191 has 16 divisors (see below), whose sum is σ = 21949747200. Its totient is φ = 18756823008.

The previous prime is 20321871131. The next prime is 20321871203. The reversal of 20321871191 is 19117812302.

It is a cyclic number.

It is not a de Polignac number, because 20321871191 - 2¹⁸ = 20321609047 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20321871131) 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 15 ways as a sum of consecutive naturals, for example, 1237130 + ... + 1253448.

It is an arithmetic number, because the mean of its divisors is an integer number (1371859200).

Almost surely, 2^20321871191 is an apocalyptic number.

20321871191 is a deficient number, since it is larger than the sum of its proper divisors (1627876009).

20321871191 is a wasteful number, since it uses less digits than its factorization.

20321871191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18238.

The product of its (nonzero) digits is 6048, while the sum is 35.

The spelling of 20321871191 in words is "twenty billion, three hundred twenty-one million, eight hundred seventy-one thousand, one hundred ninety-one".