687499999 has 4 divisors (see below), whose sum is σ = 689373664. Its totient is φ = 685626336.

The previous prime is 687499993. The next prime is 687500003. The reversal of 687499999 is 999994786.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 687499999 - 2⁷ = 687499871 is a prime.

It is a Duffinian number.

687499999 is a modest number, since divided by 99999 gives 6874 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (687499993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 936282 + ... + 937015.

It is an arithmetic number, because the mean of its divisors is an integer number (172343416).

Almost surely, 2^687499999 is an apocalyptic number.

687499999 is a deficient number, since it is larger than the sum of its proper divisors (1873665).

687499999 is a wasteful number, since it uses less digits than its factorization.

687499999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1873664.

The product of its digits is 79361856, while the sum is 70.

The square root of 687499999 is about 26220.2211851845. The cubic root of 687499999 is about 882.5870834036.

The spelling of 687499999 in words is "six hundred eighty-seven million, four hundred ninety-nine thousand, nine hundred ninety-nine".