681291868 has 6 divisors (see below), whose sum is σ = 1192260776. Its totient is φ = 340645932.

The previous prime is 681291857. The next prime is 681291869. The reversal of 681291868 is 868192186.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681291869) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 85161480 + ... + 85161487.

Almost surely, 2^681291868 is an apocalyptic number.

It is an amenable number.

681291868 is a deficient number, since it is larger than the sum of its proper divisors (510968908).

681291868 is a wasteful number, since it uses less digits than its factorization.

681291868 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 170322971 (or 170322969 counting only the distinct ones).

The product of its digits is 331776, while the sum is 49.

The square root of 681291868 is about 26101.5683053720. The cubic root of 681291868 is about 879.9224570103.

The spelling of 681291868 in words is "six hundred eighty-one million, two hundred ninety-one thousand, eight hundred sixty-eight".