687030881 has 4 divisors (see below), whose sum is σ = 687084564. Its totient is φ = 686977200.

The previous prime is 687030863. The next prime is 687030889. The reversal of 687030881 is 188030786.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 589712656 + 97318225 = 24284^2 + 9865^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-687030881 is a prime.

It is a super-2 number, since 2×687030881² = 944022862895272322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (687030889) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4751 + ... + 37371.

It is an arithmetic number, because the mean of its divisors is an integer number (171771141).

Almost surely, 2^687030881 is an apocalyptic number.

It is an amenable number.

687030881 is a deficient number, since it is larger than the sum of its proper divisors (53683).

687030881 is a wasteful number, since it uses less digits than its factorization.

687030881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53682.

The product of its (nonzero) digits is 64512, while the sum is 41.

The square root of 687030881 is about 26211.2739293610. The cubic root of 687030881 is about 882.3862922778.

The spelling of 687030881 in words is "six hundred eighty-seven million, thirty thousand, eight hundred eighty-one".