681855851 has 8 divisors (see below), whose sum is σ = 692656704. Its totient is φ = 671073480.

The previous prime is 681855841. The next prime is 681855857. The reversal of 681855851 is 158558186.

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 681855851 - 2⁶ = 681855787 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 681855796 and 681855805.

It is not an unprimeable number, because it can be changed into a prime (681855857) 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, 82556 + ... + 90438.

It is an arithmetic number, because the mean of its divisors is an integer number (86582088).

Almost surely, 2^681855851 is an apocalyptic number.

681855851 is a deficient number, since it is larger than the sum of its proper divisors (10800853).

681855851 is a wasteful number, since it uses less digits than its factorization.

681855851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9241.

The product of its digits is 384000, while the sum is 47.

The square root of 681855851 is about 26112.3696933082. The cubic root of 681855851 is about 880.1651941082.

The spelling of 681855851 in words is "six hundred eighty-one million, eight hundred fifty-five thousand, eight hundred fifty-one".