428516321 has 2 divisors, whose sum is σ = 428516322. Its totient is φ = 428516320.

The previous prime is 428516293. The next prime is 428516323. The reversal of 428516321 is 123615824.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 305550400 + 122965921 = 17480^2 + 11089^2 .

It is a cyclic number.

It is not a de Polignac number, because 428516321 - 2²⁶ = 361407457 is a prime.

Together with 428516323, it forms a pair of twin primes.

It is a Chen prime.

It is equal to p_22773542 and since 428516321 and 22773542 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (428516323) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 214258160 + 214258161.

It is an arithmetic number, because the mean of its divisors is an integer number (214258161).

Almost surely, 2^428516321 is an apocalyptic number.

It is an amenable number.

428516321 is a deficient number, since it is larger than the sum of its proper divisors (1).

428516321 is an equidigital number, since it uses as much as digits as its factorization.

428516321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11520, while the sum is 32.

The square root of 428516321 is about 20700.6357631837. The cubic root of 428516321 is about 753.9151244676.

The spelling of 428516321 in words is "four hundred twenty-eight million, five hundred sixteen thousand, three hundred twenty-one".