680999999 has 4 divisors (see below), whose sum is σ = 681302664. Its totient is φ = 680697336.

The previous prime is 680999989. The next prime is 681000013. The reversal of 680999999 is 999999086.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 999999086 = 2 ⋅499999543.

It is a cyclic number.

It is not a de Polignac number, because 680999999 - 2⁴ = 680999983 is a prime.

It is a Duffinian number.

680999999 is a modest number, since divided by 99999 gives 6809 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (680999929) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 147932 + ... + 152465.

It is an arithmetic number, because the mean of its divisors is an integer number (170325666).

Almost surely, 2^680999999 is an apocalyptic number.

680999999 is a deficient number, since it is larger than the sum of its proper divisors (302665).

680999999 is a wasteful number, since it uses less digits than its factorization.

680999999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 302664.

The product of its (nonzero) digits is 25509168, while the sum is 68.

The square root of 680999999 is about 26095.9766822397. The cubic root of 680999999 is about 879.7967846013.

The spelling of 680999999 in words is "six hundred eighty million, nine hundred ninety-nine thousand, nine hundred ninety-nine".