681668185 has 8 divisors (see below), whose sum is σ = 892365696. Its totient is φ = 495758640.

The previous prime is 681668153. The next prime is 681668191. The reversal of 681668185 is 581866186.

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

It is not a de Polignac number, because 681668185 - 2⁵ = 681668153 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6196929 + ... + 6197038.

It is an arithmetic number, because the mean of its divisors is an integer number (111545712).

Almost surely, 2^681668185 is an apocalyptic number.

It is an amenable number.

681668185 is a deficient number, since it is larger than the sum of its proper divisors (210697511).

681668185 is a wasteful number, since it uses less digits than its factorization.

681668185 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12393983.

The product of its digits is 552960, while the sum is 49.

The square root of 681668185 is about 26108.7760149724. The cubic root of 681668185 is about 880.0844379205.

It can be divided in two parts, 681 and 668185, that added together give a palindrome (668866).

The spelling of 681668185 in words is "six hundred eighty-one million, six hundred sixty-eight thousand, one hundred eighty-five".