1686674661 has 8 divisors (see below), whose sum is σ = 2570170944. Its totient is φ = 963814080.

The previous prime is 1686674659. The next prime is 1686674677. The reversal of 1686674661 is 1664766861.

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

It is not a de Polignac number, because 1686674661 - 2¹ = 1686674659 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1686674161) 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, 40158900 + ... + 40158941.

It is an arithmetic number, because the mean of its divisors is an integer number (321271368).

Almost surely, 2^1686674661 is an apocalyptic number.

It is an amenable number.

1686674661 is a deficient number, since it is larger than the sum of its proper divisors (883496283).

1686674661 is an equidigital number, since it uses as much as digits as its factorization.

1686674661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80317851.

The product of its digits is 1741824, while the sum is 51.

The square root of 1686674661 is about 41069.1448778764. The cubic root of 1686674661 is about 1190.3566619173.

The spelling of 1686674661 in words is "one billion, six hundred eighty-six million, six hundred seventy-four thousand, six hundred sixty-one".