501681820 has 12 divisors (see below), whose sum is σ = 1053531864. Its totient is φ = 200672720.

The previous prime is 501681809. The next prime is 501681823. The reversal of 501681820 is 28186105.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (501681823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12542026 + ... + 12542065.

It is an arithmetic number, because the mean of its divisors is an integer number (87794322).

Almost surely, 2^501681820 is an apocalyptic number.

It is an amenable number.

501681820 is an abundant number, since it is smaller than the sum of its proper divisors (551850044).

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

501681820 is a wasteful number, since it uses less digits than its factorization.

501681820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25084100 (or 25084098 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 31.

The square root of 501681820 is about 22398.2548427327. The cubic root of 501681820 is about 794.5894376806.

The spelling of 501681820 in words is "five hundred one million, six hundred eighty-one thousand, eight hundred twenty".