20321440131 has 4 divisors (see below), whose sum is σ = 27095253512. Its totient is φ = 13547626752.

The previous prime is 20321440099. The next prime is 20321440169. The reversal of 20321440131 is 13104412302.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 20321440131 - 2⁵ = 20321440099 is a prime.

It is a super-2 number, since 2×20321440131² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20321440098 and 20321440107.

It is not an unprimeable number, because it can be changed into a prime (20321440231) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3386906686 + ... + 3386906691.

It is an arithmetic number, because the mean of its divisors is an integer number (6773813378).

Almost surely, 2^20321440131 is an apocalyptic number.

20321440131 is a deficient number, since it is larger than the sum of its proper divisors (6773813381).

20321440131 is an equidigital number, since it uses as much as digits as its factorization.

20321440131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6773813380.

The product of its (nonzero) digits is 576, while the sum is 21.

Adding to 20321440131 its reverse (13104412302), we get a palindrome (33425852433).

The spelling of 20321440131 in words is "twenty billion, three hundred twenty-one million, four hundred forty thousand, one hundred thirty-one".