520551221 has 2 divisors, whose sum is σ = 520551222. Its totient is φ = 520551220.

The previous prime is 520551217. The next prime is 520551233. The reversal of 520551221 is 122155025.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 427910596 + 92640625 = 20686^2 + 9625^2 .

It is a cyclic number.

It is not a de Polignac number, because 520551221 - 2² = 520551217 is a prime.

It is a Chen prime.

It is equal to p_27380003 and since 520551221 and 27380003 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (520551281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260275610 + 260275611.

It is an arithmetic number, because the mean of its divisors is an integer number (260275611).

Almost surely, 2^520551221 is an apocalyptic number.

It is an amenable number.

520551221 is a deficient number, since it is larger than the sum of its proper divisors (1).

520551221 is an equidigital number, since it uses as much as digits as its factorization.

520551221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1000, while the sum is 23.

The square root of 520551221 is about 22815.5916206440. The cubic root of 520551221 is about 804.4291934882.

The spelling of 520551221 in words is "five hundred twenty million, five hundred fifty-one thousand, two hundred twenty-one".