681343781 has 8 divisors (see below), whose sum is σ = 734697600. Its totient is φ = 629739360.

The previous prime is 681343759. The next prime is 681343787. The reversal of 681343781 is 187343186.

681343781 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 681343781 - 2⁶ = 681343717 is a prime.

It is a super-2 number, since 2×681343781² = 928458695814751922, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (41).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681343787) 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, 436541 + ... + 438098.

It is an arithmetic number, because the mean of its divisors is an integer number (91837200).

Almost surely, 2^681343781 is an apocalyptic number.

It is an amenable number.

681343781 is a deficient number, since it is larger than the sum of its proper divisors (53353819).

681343781 is a wasteful number, since it uses less digits than its factorization.

681343781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 874699.

The product of its digits is 96768, while the sum is 41.

The square root of 681343781 is about 26102.5627285905. The cubic root of 681343781 is about 879.9448058530.

The spelling of 681343781 in words is "six hundred eighty-one million, three hundred forty-three thousand, seven hundred eighty-one".