16891812647 has 2 divisors, whose sum is σ = 16891812648. Its totient is φ = 16891812646.

The previous prime is 16891812557. The next prime is 16891812667. The reversal of 16891812647 is 74621819861.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 16891812647 - 2²⁰ = 16890764071 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16891812667) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8445906323 + 8445906324.

It is an arithmetic number, because the mean of its divisors is an integer number (8445906324).

Almost surely, 2^16891812647 is an apocalyptic number.

16891812647 is a deficient number, since it is larger than the sum of its proper divisors (1).

16891812647 is an equidigital number, since it uses as much as digits as its factorization.

16891812647 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1161216, while the sum is 53.

The spelling of 16891812647 in words is "sixteen billion, eight hundred ninety-one million, eight hundred twelve thousand, six hundred forty-seven".