16639697947 has 2 divisors, whose sum is σ = 16639697948. Its totient is φ = 16639697946.

The previous prime is 16639697929. The next prime is 16639697993. The reversal of 16639697947 is 74979693661.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 16639697947 - 2¹¹ = 16639695899 is a prime.

It is not a weakly prime, because it can be changed into another prime (16639697147) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8319848973 + 8319848974.

It is an arithmetic number, because the mean of its divisors is an integer number (8319848974).

Almost surely, 2^16639697947 is an apocalyptic number.

16639697947 is a deficient number, since it is larger than the sum of its proper divisors (1).

16639697947 is an equidigital number, since it uses as much as digits as its factorization.

16639697947 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 92588832, while the sum is 67.

The spelling of 16639697947 in words is "sixteen billion, six hundred thirty-nine million, six hundred ninety-seven thousand, nine hundred forty-seven".