501521521 has 4 divisors (see below), whose sum is σ = 501599232. Its totient is φ = 501443812.

The previous prime is 501521483. The next prime is 501521533. The reversal of 501521521 is 125125105.

It is a happy number.

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 501521521 - 2⁷ = 501521393 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 501521492 and 501521501.

It is not an unprimeable number, because it can be changed into a prime (501521561) 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, 28201 + ... + 42406.

It is an arithmetic number, because the mean of its divisors is an integer number (125399808).

Almost surely, 2^501521521 is an apocalyptic number.

It is an amenable number.

501521521 is a deficient number, since it is larger than the sum of its proper divisors (77711).

501521521 is an equidigital number, since it uses as much as digits as its factorization.

501521521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77710.

The product of its (nonzero) digits is 500, while the sum is 22.

The square root of 501521521 is about 22394.6761753770. The cubic root of 501521521 is about 794.5047987350.

Adding to 501521521 its reverse (125125105), we get a palindrome (626646626).

The spelling of 501521521 in words is "five hundred one million, five hundred twenty-one thousand, five hundred twenty-one".