628091 has 4 divisors (see below), whose sum is σ = 648384. Its totient is φ = 607800.

The previous prime is 628063. The next prime is 628093. The reversal of 628091 is 190826.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 190826 = 2 ⋅95413.

It is a cyclic number.

It is not a de Polignac number, because 628091 - 2¹⁴ = 611707 is a prime.

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 628091.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 628091.

It is not an unprimeable number, because it can be changed into a prime (628093) 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, 10100 + ... + 10161.

It is an arithmetic number, because the mean of its divisors is an integer number (162096).

2⁶²⁸⁰⁹¹ is an apocalyptic number.

628091 is a deficient number, since it is larger than the sum of its proper divisors (20293).

628091 is a wasteful number, since it uses less digits than its factorization.

628091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20292.

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

The square root of 628091 is about 792.5219239870. The cubic root of 628091 is about 85.6395132307.

The spelling of 628091 in words is "six hundred twenty-eight thousand, ninety-one".