501816 has 64 divisors (see below), whose sum is σ = 1497600. Its totient is φ = 137088.

The previous prime is 501803. The next prime is 501817. The reversal of 501816 is 618105.

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 odd and even.

It is a junction number, because it is equal to n+sod(n) for n = 501792 and 501801.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (501817) by changing a digit.

501816 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4821 + ... + 4923.

It is an arithmetic number, because the mean of its divisors is an integer number (23400).

2⁵⁰¹⁸¹⁶ is an apocalyptic number.

501816 is a gapful number since it is divisible by the number (56) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 501816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (748800).

501816 is an abundant number, since it is smaller than the sum of its proper divisors (995784).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

501816 is a wasteful number, since it uses less digits than its factorization.

501816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 148 (or 144 counting only the distinct ones).

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

The square root of 501816 is about 708.3897232456. The cubic root of 501816 is about 79.4660271758.

The spelling of 501816 in words is "five hundred one thousand, eight hundred sixteen".