20159238591 has 12 divisors (see below), whose sum is σ = 29134827280. Its totient is φ = 13432141440.

The previous prime is 20159238557. The next prime is 20159238641. The reversal of 20159238591 is 19583295102.

20159238591 is a `hidden beast` number, since 2 + 0 + 1 + 59 + 2 + 3 + 8 + 591 = 666.

It is not a de Polignac number, because 20159238591 - 2⁹ = 20159238079 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 (20159238391) 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 11 ways as a sum of consecutive naturals, for example, 595186 + ... + 628143.

Almost surely, 2^20159238591 is an apocalyptic number.

20159238591 is a deficient number, since it is larger than the sum of its proper divisors (8975588689).

20159238591 is a wasteful number, since it uses less digits than its factorization.

20159238591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1225166 (or 1225163 counting only the distinct ones).

The product of its (nonzero) digits is 194400, while the sum is 45.

The spelling of 20159238591 in words is "twenty billion, one hundred fifty-nine million, two hundred thirty-eight thousand, five hundred ninety-one".