20440322431 has 2 divisors, whose sum is σ = 20440322432. Its totient is φ = 20440322430.

The previous prime is 20440322429. The next prime is 20440322443. The reversal of 20440322431 is 13422304402.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20440322431 - 2¹ = 20440322429 is a prime.

It is a super-2 number, since 2×20440322431² (a number of 21 digits) contains 22 as substring.

Together with 20440322429, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 20440322396 and 20440322405.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20440322411) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10220161215 + 10220161216.

It is an arithmetic number, because the mean of its divisors is an integer number (10220161216).

Almost surely, 2^20440322431 is an apocalyptic number.

20440322431 is a deficient number, since it is larger than the sum of its proper divisors (1).

20440322431 is an equidigital number, since it uses as much as digits as its factorization.

20440322431 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4608, while the sum is 25.

Adding to 20440322431 its reverse (13422304402), we get a palindrome (33862626833).

The spelling of 20440322431 in words is "twenty billion, four hundred forty million, three hundred twenty-two thousand, four hundred thirty-one".