489981 has 4 divisors (see below), whose sum is σ = 653312. Its totient is φ = 326652.

The previous prime is 489977. The next prime is 489989. The reversal of 489981 is 189984.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 489981 - 2² = 489977 is a prime.

It is a super-2 number, since 2×489981² = 480162760722, which contains 22 as substring.

It is a D-number.

It is a Duffinian number.

489981 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (489989) 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, 81661 + ... + 81666.

It is an arithmetic number, because the mean of its divisors is an integer number (163328).

2⁴⁸⁹⁹⁸¹ is an apocalyptic number.

It is an amenable number.

489981 is a deficient number, since it is larger than the sum of its proper divisors (163331).

489981 is a wasteful number, since it uses less digits than its factorization.

489981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 163330.

The product of its digits is 20736, while the sum is 39.

The square root of 489981 is about 699.9864284399. The cubic root of 489981 is about 78.8363326317.

The spelling of 489981 in words is "four hundred eighty-nine thousand, nine hundred eighty-one".