987691 has 8 divisors (see below), whose sum is σ = 1031168. Its totient is φ = 945000.

The previous prime is 987659. The next prime is 987697. The reversal of 987691 is 196789.

987691 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 987691 - 2⁵ = 987659 is a prime.

It is a super-2 number, since 2×987691² = 1951067022962, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (987697) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4576 + ... + 4786.

It is an arithmetic number, because the mean of its divisors is an integer number (128896).

2⁹⁸⁷⁶⁹¹ is an apocalyptic number.

987691 is a deficient number, since it is larger than the sum of its proper divisors (43477).

987691 is a wasteful number, since it uses less digits than its factorization.

987691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 393.

The product of its digits is 27216, while the sum is 40.

The square root of 987691 is about 993.8264436007. The cubic root of 987691 is about 99.5880049317.

The spelling of 987691 in words is "nine hundred eighty-seven thousand, six hundred ninety-one".