20691260047 has 2 divisors, whose sum is σ = 20691260048. Its totient is φ = 20691260046.

The previous prime is 20691260041. The next prime is 20691260063. The reversal of 20691260047 is 74006219602.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20691260047 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20691259988 and 20691260015.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20691260041) 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, 10345630023 + 10345630024.

It is an arithmetic number, because the mean of its divisors is an integer number (10345630024).

Almost surely, 2^20691260047 is an apocalyptic number.

20691260047 is a deficient number, since it is larger than the sum of its proper divisors (1).

20691260047 is an equidigital number, since it uses as much as digits as its factorization.

20691260047 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 36288, while the sum is 37.

Adding to 20691260047 its reverse (74006219602), we get a palindrome (94697479649).

The spelling of 20691260047 in words is "twenty billion, six hundred ninety-one million, two hundred sixty thousand, forty-seven".