681549877966 has 16 divisors (see below), whose sum is σ = 1055697073200. Its totient is φ = 329796266688.

The previous prime is 681549877963. The next prime is 681549878003. The reversal of 681549877966 is 669778945186.

It is a junction number, because it is equal to n+sod(n) for n = 681549877892 and 681549877901.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681549877963) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 36343831 + ... + 36362578.

It is an arithmetic number, because the mean of its divisors is an integer number (65981067075).

Almost surely, 2^681549877966 is an apocalyptic number.

681549877966 is a deficient number, since it is larger than the sum of its proper divisors (374147195234).

681549877966 is a wasteful number, since it uses less digits than its factorization.

681549877966 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72706563.

The product of its digits is 1097349120, while the sum is 76.

The spelling of 681549877966 in words is "six hundred eighty-one billion, five hundred forty-nine million, eight hundred seventy-seven thousand, nine hundred sixty-six".