628109 has 4 divisors (see below), whose sum is σ = 631104. Its totient is φ = 625116.

The previous prime is 628097. The next prime is 628127. The reversal of 628109 is 901826.

628109 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 901826 = 2 ⋅450913.

It is a cyclic number.

It is not a de Polignac number, because 628109 - 2⁴ = 628093 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 628109.

It is not an unprimeable number, because it can be changed into a prime (628139) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1157 + ... + 1610.

It is an arithmetic number, because the mean of its divisors is an integer number (157776).

2⁶²⁸¹⁰⁹ is an apocalyptic number.

It is an amenable number.

628109 is a deficient number, since it is larger than the sum of its proper divisors (2995).

628109 is a wasteful number, since it uses less digits than its factorization.

628109 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2994.

The product of its (nonzero) digits is 864, while the sum is 26.

The square root of 628109 is about 792.5332800583. The cubic root of 628109 is about 85.6403313162.

It can be divided in two parts, 628 and 109, that added together give a palindrome (737).

The spelling of 628109 in words is "six hundred twenty-eight thousand, one hundred nine".