280428191 has 4 divisors (see below), whose sum is σ = 282445800. Its totient is φ = 278410584.

The previous prime is 280428119. The next prime is 280428193. The reversal of 280428191 is 191824082.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-280428191 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (280428193) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1008596 + ... + 1008873.

It is an arithmetic number, because the mean of its divisors is an integer number (70611450).

Almost surely, 2^280428191 is an apocalyptic number.

280428191 is a deficient number, since it is larger than the sum of its proper divisors (2017609).

280428191 is a wasteful number, since it uses less digits than its factorization.

280428191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2017608.

The product of its (nonzero) digits is 9216, while the sum is 35.

The square root of 280428191 is about 16745.9902961873. The cubic root of 280428191 is about 654.5465781763.

The spelling of 280428191 in words is "two hundred eighty million, four hundred twenty-eight thousand, one hundred ninety-one".