681542813 has 24 divisors (see below), whose sum is σ = 813724704. Its totient is φ = 568965600.

The previous prime is 681542803. The next prime is 681542821. The reversal of 681542813 is 318245186.

681542813 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 681542813 - 2¹⁴ = 681526429 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681542803) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 318758 + ... + 320888.

It is an arithmetic number, because the mean of its divisors is an integer number (33905196).

Almost surely, 2^681542813 is an apocalyptic number.

It is an amenable number.

681542813 is a deficient number, since it is larger than the sum of its proper divisors (132181891).

681542813 is a wasteful number, since it uses less digits than its factorization.

681542813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2313 (or 2306 counting only the distinct ones).

The product of its digits is 46080, while the sum is 38.

The square root of 681542813 is about 26106.3749494257. The cubic root of 681542813 is about 880.0304797466.

Adding to 681542813 its reverse (318245186), we get a palindrome (999787999).

The spelling of 681542813 in words is "six hundred eighty-one million, five hundred forty-two thousand, eight hundred thirteen".