20345431212647 has 2 divisors, whose sum is σ = 20345431212648. Its totient is φ = 20345431212646.

The previous prime is 20345431212637. The next prime is 20345431212671. The reversal of 20345431212647 is 74621213454302.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20345431212647 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20345431212598 and 20345431212607.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20345431212637) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10172715606323 + 10172715606324.

It is an arithmetic number, because the mean of its divisors is an integer number (10172715606324).

Almost surely, 2^{20345431212647} is an apocalyptic number.

20345431212647 is a deficient number, since it is larger than the sum of its proper divisors (1).

20345431212647 is an equidigital number, since it uses as much as digits as its factorization.

20345431212647 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 967680, while the sum is 44.

Adding to 20345431212647 its reverse (74621213454302), we get a palindrome (94966644666949).

The spelling of 20345431212647 in words is "twenty trillion, three hundred forty-five billion, four hundred thirty-one million, two hundred twelve thousand, six hundred forty-seven".