501620561 has 6 divisors (see below), whose sum is σ = 543175110. Its totient is φ = 463034208.

The previous prime is 501620503. The next prime is 501620563. The reversal of 501620561 is 165026105.

It can be written as a sum of positive squares in 3 ways, for example, as 4330561 + 497290000 = 2081^2 + 22300^2 .

It is not a de Polignac number, because 501620561 - 2¹⁰ = 501619537 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 501620561.

It is not an unprimeable number, because it can be changed into a prime (501620563) 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 5 ways as a sum of consecutive naturals, for example, 1483916 + ... + 1484253.

It is an arithmetic number, because the mean of its divisors is an integer number (90529185).

Almost surely, 2^501620561 is an apocalyptic number.

It is an amenable number.

501620561 is a deficient number, since it is larger than the sum of its proper divisors (41554549).

501620561 is a wasteful number, since it uses less digits than its factorization.

501620561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2968195 (or 2968182 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 26.

The square root of 501620561 is about 22396.8873060522. The cubic root of 501620561 is about 794.5570946471.

Adding to 501620561 its reverse (165026105), we get a palindrome (666646666).

The spelling of 501620561 in words is "five hundred one million, six hundred twenty thousand, five hundred sixty-one".