513205221 has 4 divisors (see below), whose sum is σ = 684273632. Its totient is φ = 342136812.

The previous prime is 513205183. The next prime is 513205229. The reversal of 513205221 is 122502315.

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 not a de Polignac number, because 513205221 - 2⁶ = 513205157 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 (513205229) 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, 85534201 + ... + 85534206.

It is an arithmetic number, because the mean of its divisors is an integer number (171068408).

Almost surely, 2^513205221 is an apocalyptic number.

It is an amenable number.

513205221 is a deficient number, since it is larger than the sum of its proper divisors (171068411).

513205221 is a wasteful number, since it uses less digits than its factorization.

513205221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 171068410.

The product of its (nonzero) digits is 600, while the sum is 21.

The square root of 513205221 is about 22654.0332170676. The cubic root of 513205221 is about 800.6272273746.

Adding to 513205221 its reverse (122502315), we get a palindrome (635707536).

The spelling of 513205221 in words is "five hundred thirteen million, two hundred five thousand, two hundred twenty-one".