681766877 has 12 divisors (see below), whose sum is σ = 753734940. Its totient is φ = 616186560.

The previous prime is 681766843. The next prime is 681766951. The reversal of 681766877 is 778667186.

681766877 = 15074² + 15075² + 15076².

It can be written as a sum of positive squares in 2 ways, for example, as 647906116 + 33860761 = 25454^2 + 5819^2 .

It is not a de Polignac number, because 681766877 - 2¹⁶ = 681701341 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 (681766817) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4649 + ... + 37217.

It is an arithmetic number, because the mean of its divisors is an integer number (62811245).

Almost surely, 2^681766877 is an apocalyptic number.

It is an amenable number.

681766877 is a deficient number, since it is larger than the sum of its proper divisors (71968063).

681766877 is a wasteful number, since it uses less digits than its factorization.

681766877 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32764 (or 32753 counting only the distinct ones).

The product of its digits is 4741632, while the sum is 56.

The square root of 681766877 is about 26110.6659623994. The cubic root of 681766877 is about 880.1269087804.

The spelling of 681766877 in words is "six hundred eighty-one million, seven hundred sixty-six thousand, eight hundred seventy-seven".