9987555 has 16 divisors (see below), whose sum is σ = 16085664. Its totient is φ = 5291520.

The previous prime is 9987553. The next prime is 9987569. The reversal of 9987555 is 5557899.

9987555 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 9987555 - 2¹ = 9987553 is a prime.

It is a nialpdrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9987553) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 235 + ... + 4475.

It is an arithmetic number, because the mean of its divisors is an integer number (1005354).

Almost surely, 2^9987555 is an apocalyptic number.

9987555 is a deficient number, since it is larger than the sum of its proper divisors (6098109).

9987555 is a wasteful number, since it uses less digits than its factorization.

9987555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4406.

The product of its digits is 567000, while the sum is 48.

The square root of 9987555 is about 3160.3093203039. The cubic root of 9987555 is about 215.3540587702.

It can be divided in two parts, 9987 and 555, that multiplied together give a triangular number (5542785 = T₃₃₂₉).

The spelling of 9987555 in words is "nine million, nine hundred eighty-seven thousand, five hundred fifty-five".