205421351 has 2 divisors, whose sum is σ = 205421352. Its totient is φ = 205421350.

The previous prime is 205421341. The next prime is 205421399. The reversal of 205421351 is 153124502.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 205421351 - 2²⁶ = 138312487 is a prime.

It is a Chen prime.

It is equal to p_11362442 and since 205421351 and 11362442 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 (205421311) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102710675 + 102710676.

It is an arithmetic number, because the mean of its divisors is an integer number (102710676).

Almost surely, 2^205421351 is an apocalyptic number.

205421351 is a deficient number, since it is larger than the sum of its proper divisors (1).

205421351 is an equidigital number, since it uses as much as digits as its factorization.

205421351 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1200, while the sum is 23.

The square root of 205421351 is about 14332.5277254223. The cubic root of 205421351 is about 590.0405516511.

Adding to 205421351 its reverse (153124502), we get a palindrome (358545853).

The spelling of 205421351 in words is "two hundred five million, four hundred twenty-one thousand, three hundred fifty-one".