99999999647 has 2 divisors, whose sum is σ = 99999999648. Its totient is φ = 99999999646.

The previous prime is 99999999599. The next prime is 99999999653. The reversal of 99999999647 is 74699999999.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 99999999647 - 2⁸ = 99999999391 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (99999999667) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49999999823 + 49999999824.

It is an arithmetic number, because the mean of its divisors is an integer number (49999999824).

Almost surely, 2^99999999647 is an apocalyptic number.

99999999647 is a deficient number, since it is larger than the sum of its proper divisors (1).

99999999647 is an equidigital number, since it uses as much as digits as its factorization.

99999999647 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7231849128, while the sum is 89.

The spelling of 99999999647 in words is "ninety-nine billion, nine hundred ninety-nine million, nine hundred ninety-nine thousand, six hundred forty-seven".