987990 has 16 divisors (see below), whose sum is σ = 2371248. Its totient is φ = 263456.

The previous prime is 987983. The next prime is 987991. The reversal of 987990 is 99789.

It is a happy number.

It is a super-2 number, since 2×987990² = 1952248480200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (987991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16437 + ... + 16496.

It is an arithmetic number, because the mean of its divisors is an integer number (148203).

2⁹⁸⁷⁹⁹⁰ is an apocalyptic number.

987990 is an abundant number, since it is smaller than the sum of its proper divisors (1383258).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

987990 is a wasteful number, since it uses less digits than its factorization.

987990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32943.

The product of its (nonzero) digits is 40824, while the sum is 42.

The square root of 987990 is about 993.9768608977. The cubic root of 987990 is about 99.5980532192.

The spelling of 987990 in words is "nine hundred eighty-seven thousand, nine hundred ninety".