428191 has 4 divisors (see below), whose sum is σ = 446832. Its totient is φ = 409552.

The previous prime is 428177. The next prime is 428221. The reversal of 428191 is 191824.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 428191 - 2¹³ = 419999 is a prime.

It is a Duffinian number.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (428161) 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, 9286 + ... + 9331.

It is an arithmetic number, because the mean of its divisors is an integer number (111708).

2⁴²⁸¹⁹¹ is an apocalyptic number.

428191 is a deficient number, since it is larger than the sum of its proper divisors (18641).

428191 is a wasteful number, since it uses less digits than its factorization.

428191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18640.

The product of its digits is 576, while the sum is 25.

The square root of 428191 is about 654.3630490790. The cubic root of 428191 is about 75.3724290418.

The spelling of 428191 in words is "four hundred twenty-eight thousand, one hundred ninety-one".