987761 has 4 divisors (see below), whose sum is σ = 1006452. Its totient is φ = 969072.

The previous prime is 987739. The next prime is 987793. The reversal of 987761 is 167789.

It is a happy number.

987761 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 167789 = 19 ⋅8831.

It can be written as a sum of positive squares in 2 ways, for example, as 255025 + 732736 = 505^2 + 856^2 .

It is a cyclic number.

It is not a de Polignac number, because 987761 - 2⁶ = 987697 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 10.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 987761.

It is not an unprimeable number, because it can be changed into a prime (987061) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9266 + ... + 9371.

It is an arithmetic number, because the mean of its divisors is an integer number (251613).

2⁹⁸⁷⁷⁶¹ is an apocalyptic number.

It is an amenable number.

987761 is a deficient number, since it is larger than the sum of its proper divisors (18691).

987761 is a wasteful number, since it uses less digits than its factorization.

987761 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18690.

The product of its digits is 21168, while the sum is 38.

The square root of 987761 is about 993.8616603934. The cubic root of 987761 is about 99.5903575554.

The spelling of 987761 in words is "nine hundred eighty-seven thousand, seven hundred sixty-one".