16771639649 has 4 divisors (see below), whose sum is σ = 16792019136. Its totient is φ = 16751260164.

The previous prime is 16771639607. The next prime is 16771639657. The reversal of 16771639649 is 94693617761.

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.

It is a cyclic number.

It is not a de Polignac number, because 16771639649 - 2⁸ = 16771639393 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (16771639349) 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, 10188509 + ... + 10190154.

It is an arithmetic number, because the mean of its divisors is an integer number (4198004784).

Almost surely, 2^16771639649 is an apocalyptic number.

It is an amenable number.

16771639649 is a deficient number, since it is larger than the sum of its proper divisors (20379487).

16771639649 is an equidigital number, since it uses as much as digits as its factorization.

16771639649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20379486.

The product of its digits is 10287648, while the sum is 59.

The spelling of 16771639649 in words is "sixteen billion, seven hundred seventy-one million, six hundred thirty-nine thousand, six hundred forty-nine".