9890 has 16 divisors (see below), whose sum is σ = 19008. Its totient is φ = 3696.

The previous prime is 9887. The next prime is 9901. The reversal of 9890 is 989.

9890 = 23² + 24² + ... + 34².

It is a happy number.

It is an alternating number because its digits alternate between odd and even.

It is a plaindrome in base 13.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 209 + ... + 251.

It is an arithmetic number, because the mean of its divisors is an integer number (1188).

2⁹⁸⁹⁰ is an apocalyptic number.

9890 is a deficient number, since it is larger than the sum of its proper divisors (9118).

9890 is a wasteful number, since it uses less digits than its factorization.

9890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73.

The product of its (nonzero) digits is 648, while the sum is 26.

The square root of 9890 is about 99.4484791236. The cubic root of 9890 is about 21.4650595267.

The spelling of 9890 in words is "nine thousand, eight hundred ninety".