521688229 has 2 divisors, whose sum is σ = 521688230. Its totient is φ = 521688228.

The previous prime is 521688173. The next prime is 521688281. The reversal of 521688229 is 922886125.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 495952900 + 25735329 = 22270^2 + 5073^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-521688229 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (521688029) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 260844114 + 260844115.

It is an arithmetic number, because the mean of its divisors is an integer number (260844115).

Almost surely, 2^521688229 is an apocalyptic number.

It is an amenable number.

521688229 is a deficient number, since it is larger than the sum of its proper divisors (1).

521688229 is an equidigital number, since it uses as much as digits as its factorization.

521688229 is an evil number, because the sum of its binary digits is even.

The product of its digits is 138240, while the sum is 43.

The square root of 521688229 is about 22840.4953755386. The cubic root of 521688229 is about 805.0144559728.

The spelling of 521688229 in words is "five hundred twenty-one million, six hundred eighty-eight thousand, two hundred twenty-nine".