21676660171 has 4 divisors (see below), whose sum is σ = 21737041200. Its totient is φ = 21616279144.

The previous prime is 21676660153. The next prime is 21676660219. The reversal of 21676660171 is 17106667612.

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

It is a cyclic number.

It is not a de Polignac number, because 21676660171 - 2⁵ = 21676660139 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21676660141) 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, 30189976 + ... + 30190693.

It is an arithmetic number, because the mean of its divisors is an integer number (5434260300).

Almost surely, 2^21676660171 is an apocalyptic number.

21676660171 is a deficient number, since it is larger than the sum of its proper divisors (60381029).

21676660171 is an equidigital number, since it uses as much as digits as its factorization.

21676660171 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60381028.

The product of its (nonzero) digits is 127008, while the sum is 43.

The spelling of 21676660171 in words is "twenty-one billion, six hundred seventy-six million, six hundred sixty thousand, one hundred seventy-one".