16661052447771 has 4 divisors (see below), whose sum is σ = 22214736597032. Its totient is φ = 11107368298512.

The previous prime is 16661052447763. The next prime is 16661052447797. The reversal of 16661052447771 is 17774425016661.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 16661052447771 - 2³ = 16661052447763 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16661052447671) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2776842074626 + ... + 2776842074631.

It is an arithmetic number, because the mean of its divisors is an integer number (5553684149258).

Almost surely, 2^{16661052447771} is an apocalyptic number.

16661052447771 is a deficient number, since it is larger than the sum of its proper divisors (5553684149261).

16661052447771 is an equidigital number, since it uses as much as digits as its factorization.

16661052447771 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5553684149260.

The product of its (nonzero) digits is 11854080, while the sum is 57.

The spelling of 16661052447771 in words is "sixteen trillion, six hundred sixty-one billion, fifty-two million, four hundred forty-seven thousand, seven hundred seventy-one".