686687090 has 8 divisors (see below), whose sum is σ = 1236036780. Its totient is φ = 274674832.

The previous prime is 686687083. The next prime is 686687117. The reversal of 686687090 is 90786686.

It can be written as a sum of positive squares in 2 ways, for example, as 684397921 + 2289169 = 26161^2 + 1513^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34334345 + ... + 34334364.

Almost surely, 2^686687090 is an apocalyptic number.

686687090 is a deficient number, since it is larger than the sum of its proper divisors (549349690).

686687090 is a wasteful number, since it uses less digits than its factorization.

686687090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68668716.

The product of its (nonzero) digits is 870912, while the sum is 50.

The square root of 686687090 is about 26204.7150337492. The cubic root of 686687090 is about 882.2390853675.

The spelling of 686687090 in words is "six hundred eighty-six million, six hundred eighty-seven thousand, ninety".