501987 has 4 divisors (see below), whose sum is σ = 669320. Its totient is φ = 334656.

The previous prime is 501971. The next prime is 501997. The reversal of 501987 is 789105.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 501987 - 2⁴ = 501971 is a prime.

It is a D-number.

It is a Duffinian number.

501987 is a lucky number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 501987.

It is not an unprimeable number, because it can be changed into a prime (501947) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 83662 + ... + 83667.

It is an arithmetic number, because the mean of its divisors is an integer number (167330).

2⁵⁰¹⁹⁸⁷ is an apocalyptic number.

501987 is a deficient number, since it is larger than the sum of its proper divisors (167333).

501987 is a wasteful number, since it uses less digits than its factorization.

501987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 167332.

The product of its (nonzero) digits is 2520, while the sum is 30.

The square root of 501987 is about 708.5104092390. The cubic root of 501987 is about 79.4750524941.

It can be divided in two parts, 50198 and 7, that added together give a palindrome (50205).

The spelling of 501987 in words is "five hundred one thousand, nine hundred eighty-seven".