513122221 has 2 divisors, whose sum is σ = 513122222. Its totient is φ = 513122220.

The previous prime is 513122219. The next prime is 513122251. The reversal of 513122221 is 122221315.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 511392996 + 1729225 = 22614^2 + 1315^2 .

It is a cyclic number.

It is not a de Polignac number, because 513122221 - 2¹ = 513122219 is a prime.

Together with 513122219, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (513122251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 256561110 + 256561111.

It is an arithmetic number, because the mean of its divisors is an integer number (256561111).

Almost surely, 2^513122221 is an apocalyptic number.

It is an amenable number.

513122221 is a deficient number, since it is larger than the sum of its proper divisors (1).

513122221 is an equidigital number, since it uses as much as digits as its factorization.

513122221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 240, while the sum is 19.

The square root of 513122221 is about 22652.2012396147. The cubic root of 513122221 is about 800.5840635876.

Adding to 513122221 its reverse (122221315), we get a palindrome (635343536).

The spelling of 513122221 in words is "five hundred thirteen million, one hundred twenty-two thousand, two hundred twenty-one".