671671051661 has 8 divisors (see below), whose sum is σ = 679457082240. Its totient is φ = 663890336032.

The previous prime is 671671051657. The next prime is 671671051673. The reversal of 671671051661 is 166150176176.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 671671051661 - 2² = 671671051657 is a prime.

It is a super-2 number, since 2×671671051661² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (671671051651) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1074245 + ... + 1580298.

It is an arithmetic number, because the mean of its divisors is an integer number (84932135280).

Almost surely, 2^671671051661 is an apocalyptic number.

It is an amenable number.

671671051661 is a deficient number, since it is larger than the sum of its proper divisors (7786030579).

671671051661 is a wasteful number, since it uses less digits than its factorization.

671671051661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2657475.

The product of its (nonzero) digits is 317520, while the sum is 47.

The spelling of 671671051661 in words is "six hundred seventy-one billion, six hundred seventy-one million, fifty-one thousand, six hundred sixty-one".