987557 has 4 divisors (see below), whose sum is σ = 997836. Its totient is φ = 977280.

The previous prime is 987541. The next prime is 987559. The reversal of 987557 is 755789.

It is a happy number.

987557 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.

It can be written as a sum of positive squares in 2 ways, for example, as 516961 + 470596 = 719^2 + 686^2 .

It is a cyclic number.

It is not a de Polignac number, because 987557 - 2⁴ = 987541 is a prime.

It is a Duffinian number.

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 987557.

It is not an unprimeable number, because it can be changed into a prime (987559) 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, 4994 + ... + 5187.

It is an arithmetic number, because the mean of its divisors is an integer number (249459).

2⁹⁸⁷⁵⁵⁷ is an apocalyptic number.

987557 is a gapful number since it is divisible by the number (97) formed by its first and last digit.

It is an amenable number.

987557 is a deficient number, since it is larger than the sum of its proper divisors (10279).

987557 is a wasteful number, since it uses less digits than its factorization.

987557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10278.

The product of its digits is 88200, while the sum is 41.

The square root of 987557 is about 993.7590251163. The cubic root of 987557 is about 99.5835010277.

The spelling of 987557 in words is "nine hundred eighty-seven thousand, five hundred fifty-seven".