680288781 has 4 divisors (see below), whose sum is σ = 907051712. Its totient is φ = 453525852.

The previous prime is 680288747. The next prime is 680288783. The reversal of 680288781 is 187882086.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 680288781 - 2⁶ = 680288717 is a prime.

It is a super-2 number, since 2×680288781² = 925585651108931922, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 680288781.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (680288783) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 113381461 + ... + 113381466.

It is an arithmetic number, because the mean of its divisors is an integer number (226762928).

Almost surely, 2^680288781 is an apocalyptic number.

It is an amenable number.

680288781 is a deficient number, since it is larger than the sum of its proper divisors (226762931).

680288781 is a wasteful number, since it uses less digits than its factorization.

680288781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 226762930.

The product of its (nonzero) digits is 344064, while the sum is 48.

The square root of 680288781 is about 26082.3461559730. The cubic root of 680288781 is about 879.4903992523.

The spelling of 680288781 in words is "six hundred eighty million, two hundred eighty-eight thousand, seven hundred eighty-one".