16643522671 has 2 divisors, whose sum is σ = 16643522672. Its totient is φ = 16643522670.

The previous prime is 16643522659. The next prime is 16643522677. The reversal of 16643522671 is 17622534661.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 16643522671 - 2¹⁷ = 16643391599 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16643522677) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8321761335 + 8321761336.

It is an arithmetic number, because the mean of its divisors is an integer number (8321761336).

Almost surely, 2^16643522671 is an apocalyptic number.

16643522671 is a deficient number, since it is larger than the sum of its proper divisors (1).

16643522671 is an equidigital number, since it uses as much as digits as its factorization.

16643522671 is an evil number, because the sum of its binary digits is even.

The product of its digits is 362880, while the sum is 43.

The spelling of 16643522671 in words is "sixteen billion, six hundred forty-three million, five hundred twenty-two thousand, six hundred seventy-one".