680867861 has 8 divisors (see below), whose sum is σ = 690939480. Its totient is φ = 670816512.

The previous prime is 680867843. The next prime is 680867903. The reversal of 680867861 is 168768086.

It can be written as a sum of positive squares in 4 ways, for example, as 539400625 + 141467236 = 23225^2 + 11894^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-680867861 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 (680860861) 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, 70895 + ... + 79923.

It is an arithmetic number, because the mean of its divisors is an integer number (86367435).

Almost surely, 2^680867861 is an apocalyptic number.

It is an amenable number.

680867861 is a deficient number, since it is larger than the sum of its proper divisors (10071619).

680867861 is a wasteful number, since it uses less digits than its factorization.

680867861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10135.

The product of its (nonzero) digits is 774144, while the sum is 50.

The square root of 680867861 is about 26093.4447898318. Note that the first 3 decimals coincide. The cubic root of 680867861 is about 879.7398770596.

The spelling of 680867861 in words is "six hundred eighty million, eight hundred sixty-seven thousand, eight hundred sixty-one".