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, and also an emirpimes, since its reverse is a distinct semiprime: 168094 = 2 ⋅84047.
It is a cyclic number.
It is a Duffinian number.
It is a congruent number.
2490861 is an apocalyptic number.
490861 is the 405-th hex number.
It is an amenable number.
490861 is an equidigital number, since it uses as much as digits as its factorization.
490861 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 70130.
The square root of 490861 is about 700.6147300764. The cubic root of 490861 is about 78.8835007745.
The spelling of 490861 in words is "four hundred ninety thousand, eight hundred sixty-one".