16946672221 has 2 divisors, whose sum is σ = 16946672222. Its totient is φ = 16946672220.

The previous prime is 16946672219. The next prime is 16946672227. The reversal of 16946672221 is 12227664961.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14283596196 + 2663076025 = 119514^2 + 51605^2 .

It is a cyclic number.

It is not a de Polignac number, because 16946672221 - 2¹ = 16946672219 is a prime.

Together with 16946672219, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16946672227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8473336110 + 8473336111.

It is an arithmetic number, because the mean of its divisors is an integer number (8473336111).

Almost surely, 2^16946672221 is an apocalyptic number.

It is an amenable number.

16946672221 is a deficient number, since it is larger than the sum of its proper divisors (1).

16946672221 is an equidigital number, since it uses as much as digits as its factorization.

16946672221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 435456, while the sum is 46.

The spelling of 16946672221 in words is "sixteen billion, nine hundred forty-six million, six hundred seventy-two thousand, two hundred twenty-one".