205421329 has 2 divisors, whose sum is σ = 205421330. Its totient is φ = 205421328.

The previous prime is 205421327. The next prime is 205421339. The reversal of 205421329 is 923124502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 122611329 + 82810000 = 11073^2 + 9100^2 .

It is a cyclic number.

It is not a de Polignac number, because 205421329 - 2¹ = 205421327 is a prime.

Together with 205421327, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 205421297 and 205421306.

It is not a weakly prime, because it can be changed into another prime (205421327) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102710664 + 102710665.

It is an arithmetic number, because the mean of its divisors is an integer number (102710665).

Almost surely, 2^205421329 is an apocalyptic number.

It is an amenable number.

205421329 is a deficient number, since it is larger than the sum of its proper divisors (1).

205421329 is an equidigital number, since it uses as much as digits as its factorization.

205421329 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 205421329 is about 14332.5269579373. The cubic root of 205421329 is about 590.0405305873.

The spelling of 205421329 in words is "two hundred five million, four hundred twenty-one thousand, three hundred twenty-nine".