671444219889 has 27 divisors (see below), whose sum is σ = 1030334746987. Its totient is φ = 421272112704.

The previous prime is 671444219881. The next prime is 671444219891. The reversal of 671444219889 is 988912444176.

The square root of 671444219889 is 819417.

It is a perfect power (a square), and thus also a powerful number.

671444219889 is a `hidden beast` number, since 6 + 7 + 1 + 44 + 421 + 98 + 89 = 666.

It can be written as a sum of positive squares in only one way, i.e., 522750690225 + 148693529664 = 723015^2 + 385608^2 .

It is not a de Polignac number, because 671444219889 - 2³ = 671444219881 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 (671444219881) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 41782234 + ... + 41798300.

Almost surely, 2^671444219889 is an apocalyptic number.

671444219889 is the 819417-th square number.

671444219889 is the 409709-th centered octagonal number.

It is an amenable number.

671444219889 is a deficient number, since it is larger than the sum of its proper divisors (358890527098).

671444219889 is an frugal number, since it uses more digits than its factorization.

671444219889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32174 (or 16087 counting only the distinct ones).

The product of its digits is 27869184, while the sum is 63.

The spelling of 671444219889 in words is "six hundred seventy-one billion, four hundred forty-four million, two hundred nineteen thousand, eight hundred eighty-nine".