20423131447 has 2 divisors, whose sum is σ = 20423131448. Its totient is φ = 20423131446.

The previous prime is 20423131403. The next prime is 20423131457. The reversal of 20423131447 is 74413132402.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20423131447 - 2¹¹ = 20423129399 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20423131457) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10211565723 + 10211565724.

It is an arithmetic number, because the mean of its divisors is an integer number (10211565724).

Almost surely, 2^20423131447 is an apocalyptic number.

20423131447 is a deficient number, since it is larger than the sum of its proper divisors (1).

20423131447 is an equidigital number, since it uses as much as digits as its factorization.

20423131447 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16128, while the sum is 31.

Adding to 20423131447 its reverse (74413132402), we get a palindrome (94836263849).

The spelling of 20423131447 in words is "twenty billion, four hundred twenty-three million, one hundred thirty-one thousand, four hundred forty-seven".