505530021 has 8 divisors (see below), whose sum is σ = 680005440. Its totient is φ = 334037312.

The previous prime is 505530019. The next prime is 505530023. The reversal of 505530021 is 120035505.

It is an interprime number because it is at equal distance from previous prime (505530019) and next prime (505530023).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 505530021 - 2¹ = 505530019 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 505530021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (505530023) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 745281 + ... + 745958.

It is an arithmetic number, because the mean of its divisors is an integer number (85000680).

Almost surely, 2^505530021 is an apocalyptic number.

It is an amenable number.

505530021 is a deficient number, since it is larger than the sum of its proper divisors (174475419).

505530021 is a wasteful number, since it uses less digits than its factorization.

505530021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1491355.

The product of its (nonzero) digits is 750, while the sum is 21.

The square root of 505530021 is about 22483.9947740609. The cubic root of 505530021 is about 796.6159244966.

Adding to 505530021 its reverse (120035505), we get a palindrome (625565526).

The spelling of 505530021 in words is "five hundred five million, five hundred thirty thousand, twenty-one".