16688621977 has 2 divisors, whose sum is σ = 16688621978. Its totient is φ = 16688621976.

The previous prime is 16688621947. The next prime is 16688622007. The reversal of 16688621977 is 77912688661.

16688621977 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a balanced prime because it is at equal distance from previous prime (16688621947) and next prime (16688622007).

It can be written as a sum of positive squares in only one way, i.e., 13708663056 + 2979958921 = 117084^2 + 54589^2 .

It is a cyclic number.

It is not a de Polignac number, because 16688621977 - 2⁷ = 16688621849 is a prime.

It is not a weakly prime, because it can be changed into another prime (16688621947) 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, 8344310988 + 8344310989.

It is an arithmetic number, because the mean of its divisors is an integer number (8344310989).

Almost surely, 2^16688621977 is an apocalyptic number.

It is an amenable number.

16688621977 is a deficient number, since it is larger than the sum of its proper divisors (1).

16688621977 is an equidigital number, since it uses as much as digits as its factorization.

16688621977 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12192768, while the sum is 61.

The spelling of 16688621977 in words is "sixteen billion, six hundred eighty-eight million, six hundred twenty-one thousand, nine hundred seventy-seven".