1686666852 has 36 divisors (see below), whose sum is σ = 4591483260. Its totient is φ = 518974272.

The previous prime is 1686666851. The next prime is 1686666881. The reversal of 1686666852 is 2586666861.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 681523236 + 1005143616 = 26106^2 + 31704^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is not an unprimeable number, because it can be changed into a prime (1686666851) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1801527 + ... + 1802462.

Almost surely, 2^1686666852 is an apocalyptic number.

1686666852 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1686666852 is an abundant number, since it is smaller than the sum of its proper divisors (2904816408).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1686666852 is a wasteful number, since it uses less digits than its factorization.

1686666852 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3604012 (or 3604007 counting only the distinct ones).

The product of its digits is 4976640, while the sum is 54.

The square root of 1686666852 is about 41069.0498063931. The cubic root of 1686666852 is about 1190.3548248687.

Subtracting 1686666852 from its reverse (2586666861), we obtain a palindrome (900000009).

The spelling of 1686666852 in words is "one billion, six hundred eighty-six million, six hundred sixty-six thousand, eight hundred fifty-two".