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: 127418 = 2 ⋅63709.
It is a cyclic number.
It is an alternating number because its digits alternate between even and odd.
It is a Duffinian number.
It is a plaindrome in base 13.
It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 814721.
2814721 is an apocalyptic number.
It is an amenable number.
814721 is a wasteful number, since it uses less digits than its factorization.
814721 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 18990.
The square root of 814721 is about 902.6189672281. The cubic root of 814721 is about 93.3977262552.
The spelling of 814721 in words is "eight hundred fourteen thousand, seven hundred twenty-one".