505600021 has 4 divisors (see below), whose sum is σ = 505746112. Its totient is φ = 505453932.

The previous prime is 505600001. The next prime is 505600031. The reversal of 505600021 is 120006505.

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 505600021 - 2⁵ = 505599989 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (505600001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 67725 + ... + 74818.

It is an arithmetic number, because the mean of its divisors is an integer number (126436528).

Almost surely, 2^505600021 is an apocalyptic number.

It is an amenable number.

505600021 is a deficient number, since it is larger than the sum of its proper divisors (146091).

505600021 is a wasteful number, since it uses less digits than its factorization.

505600021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 146090.

The product of its (nonzero) digits is 300, while the sum is 19.

The square root of 505600021 is about 22485.5513830549. The cubic root of 505600021 is about 796.6526915456.

Adding to 505600021 its reverse (120006505), we get a palindrome (625606526).

The spelling of 505600021 in words is "five hundred five million, six hundred thousand, twenty-one".