628405 has 8 divisors (see below), whose sum is σ = 798552. Its totient is φ = 473088.

The previous prime is 628399. The next prime is 628423. The reversal of 628405 is 504826.

It can be written as a sum of positive squares in 4 ways, for example, as 49284 + 579121 = 222^2 + 761^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 628405 - 2⁵ = 628373 is a prime.

It is a d-powerful number, because it can be written as 6⁷ + 2¹³ + 4⁹ + 8 + 0 + 5⁷ .

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 628405.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3612 + ... + 3781.

It is an arithmetic number, because the mean of its divisors is an integer number (99819).

2⁶²⁸⁴⁰⁵ is an apocalyptic number.

It is an amenable number.

628405 is a deficient number, since it is larger than the sum of its proper divisors (170147).

628405 is a wasteful number, since it uses less digits than its factorization.

628405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7415.

The product of its (nonzero) digits is 1920, while the sum is 25.

The square root of 628405 is about 792.7200010092. The cubic root of 628405 is about 85.6537820374.

The spelling of 628405 in words is "six hundred twenty-eight thousand, four hundred five".