16801666555 has 4 divisors (see below), whose sum is σ = 20161999872. Its totient is φ = 13441333240.

The previous prime is 16801666537. The next prime is 16801666573. The reversal of 16801666555 is 55566610861.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 55566610861 = 6367 ⋅8727283.

It is an interprime number because it is at equal distance from previous prime (16801666537) and next prime (16801666573).

It is not a de Polignac number, because 16801666555 - 2¹¹ = 16801664507 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 16801666499 and 16801666508.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1680166651 + ... + 1680166660.

It is an arithmetic number, because the mean of its divisors is an integer number (5040499968).

Almost surely, 2^16801666555 is an apocalyptic number.

16801666555 is a deficient number, since it is larger than the sum of its proper divisors (3360333317).

16801666555 is an equidigital number, since it uses as much as digits as its factorization.

16801666555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3360333316.

The product of its (nonzero) digits is 1296000, while the sum is 49.

The spelling of 16801666555 in words is "sixteen billion, eight hundred one million, six hundred sixty-six thousand, five hundred fifty-five".