628821289 has 2 divisors, whose sum is σ = 628821290. Its totient is φ = 628821288.

The previous prime is 628821287. The next prime is 628821341. The reversal of 628821289 is 982128826.

628821289 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 525188889 + 103632400 = 22917^2 + 10180^2 .

It is a cyclic number.

It is not a de Polignac number, because 628821289 - 2¹ = 628821287 is a prime.

Together with 628821287, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (628821287) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 314410644 + 314410645.

It is an arithmetic number, because the mean of its divisors is an integer number (314410645).

Almost surely, 2^628821289 is an apocalyptic number.

It is an amenable number.

628821289 is a deficient number, since it is larger than the sum of its proper divisors (1).

628821289 is an equidigital number, since it uses as much as digits as its factorization.

628821289 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 221184, while the sum is 46.

The square root of 628821289 is about 25076.3093177605. The cubic root of 628821289 is about 856.7269174081.

The spelling of 628821289 in words is "six hundred twenty-eight million, eight hundred twenty-one thousand, two hundred eighty-nine".