628820389 has 2 divisors, whose sum is σ = 628820390. Its totient is φ = 628820388.

The previous prime is 628820341. The next prime is 628820431. The reversal of 628820389 is 983028826.

It is a happy number.

628820389 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 504676225 + 124144164 = 22465^2 + 11142^2 .

It is a cyclic number.

It is not a de Polignac number, because 628820389 - 2¹⁹ = 628296101 is a prime.

It is a super-2 number, since 2×628820389² = 790830163244222642, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (628823389) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 314410194 + 314410195.

It is an arithmetic number, because the mean of its divisors is an integer number (314410195).

Almost surely, 2^628820389 is an apocalyptic number.

It is an amenable number.

628820389 is a deficient number, since it is larger than the sum of its proper divisors (1).

628820389 is an equidigital number, since it uses as much as digits as its factorization.

628820389 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 331776, while the sum is 46.

The square root of 628820389 is about 25076.2913725296. The cubic root of 628820389 is about 856.7265086780.

The spelling of 628820389 in words is "six hundred twenty-eight million, eight hundred twenty thousand, three hundred eighty-nine".