687394989 has 12 divisors (see below), whose sum is σ = 993862272. Its totient is φ = 457821000.

The previous prime is 687394987. The next prime is 687394999. The reversal of 687394989 is 989493786.

687394989 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 687394989 - 2¹ = 687394987 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (687394987) 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, 26877 + ... + 45794.

It is an arithmetic number, because the mean of its divisors is an integer number (82821856).

Almost surely, 2^687394989 is an apocalyptic number.

It is an amenable number.

687394989 is a deficient number, since it is larger than the sum of its proper divisors (306467283).

687394989 is a wasteful number, since it uses less digits than its factorization.

687394989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73728 (or 73725 counting only the distinct ones).

The product of its digits is 23514624, while the sum is 63.

The square root of 687394989 is about 26218.2186465824. The cubic root of 687394989 is about 882.5421451302.

The spelling of 687394989 in words is "six hundred eighty-seven million, three hundred ninety-four thousand, nine hundred eighty-nine".