501385561 has 4 divisors (see below), whose sum is σ = 501984000. Its totient is φ = 500787124.

The previous prime is 501385559. The next prime is 501385571. The reversal of 501385561 is 165583105.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 501385561 - 2¹ = 501385559 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (501385541) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 297961 + ... + 299638.

It is an arithmetic number, because the mean of its divisors is an integer number (125496000).

Almost surely, 2^501385561 is an apocalyptic number.

It is an amenable number.

501385561 is a deficient number, since it is larger than the sum of its proper divisors (598439).

501385561 is an equidigital number, since it uses as much as digits as its factorization.

501385561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 598438.

The product of its (nonzero) digits is 18000, while the sum is 34.

The square root of 501385561 is about 22391.6404267307. The cubic root of 501385561 is about 794.4329968078.

The spelling of 501385561 in words is "five hundred one million, three hundred eighty-five thousand, five hundred sixty-one".