16571216689 has 4 divisors (see below), whose sum is σ = 16571496256. Its totient is φ = 16570937124.

The previous prime is 16571216653. The next prime is 16571216729. The reversal of 16571216689 is 98661217561.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 98661217561 = 17 ⋅5803601033.

It is a cyclic number.

It is not a de Polignac number, because 16571216689 - 2⁷ = 16571216561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16571219689) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11829 + ... + 182434.

It is an arithmetic number, because the mean of its divisors is an integer number (4142874064).

Almost surely, 2^16571216689 is an apocalyptic number.

It is an amenable number.

16571216689 is a deficient number, since it is larger than the sum of its proper divisors (279567).

16571216689 is an equidigital number, since it uses as much as digits as its factorization.

16571216689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 279566.

The product of its digits is 1088640, while the sum is 52.

The spelling of 16571216689 in words is "sixteen billion, five hundred seventy-one million, two hundred sixteen thousand, six hundred eighty-nine".