671606644 has 6 divisors (see below), whose sum is σ = 1175311634. Its totient is φ = 335803320.

The previous prime is 671606633. The next prime is 671606657. The reversal of 671606644 is 446606176.

It is a happy number.

671606644 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 453690000 + 217916644 = 21300^2 + 14762^2 .

It is a super-3 number, since 3×671606644³ (a number of 27 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 671606597 and 671606606.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83950827 + ... + 83950834.

Almost surely, 2^671606644 is an apocalyptic number.

It is an amenable number.

671606644 is a deficient number, since it is larger than the sum of its proper divisors (503704990).

671606644 is a wasteful number, since it uses less digits than its factorization.

671606644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 167901665 (or 167901663 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 40.

The square root of 671606644 is about 25915.3746644728. The cubic root of 671606644 is about 875.7328908377.

The spelling of 671606644 in words is "six hundred seventy-one million, six hundred six thousand, six hundred forty-four".