816501 has 16 divisors (see below), whose sum is σ = 1267200. Its totient is φ = 457968.

The previous prime is 816499. The next prime is 816521. The reversal of 816501 is 105618.

It is not a de Polignac number, because 816501 - 2¹ = 816499 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

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

816501 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (816521) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 910 + ... + 1568.

It is an arithmetic number, because the mean of its divisors is an integer number (79200).

2⁸¹⁶⁵⁰¹ is an apocalyptic number.

It is an amenable number.

816501 is a deficient number, since it is larger than the sum of its proper divisors (450699).

816501 is a wasteful number, since it uses less digits than its factorization.

816501 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 728.

The product of its (nonzero) digits is 240, while the sum is 21.

The square root of 816501 is about 903.6044488602. The cubic root of 816501 is about 93.4656951373.

The spelling of 816501 in words is "eight hundred sixteen thousand, five hundred one".