8420591 has 4 divisors (see below), whose sum is σ = 8863800. Its totient is φ = 7977384.

The previous prime is 8420569. The next prime is 8420597. The reversal of 8420591 is 1950248.

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-8420591 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 (8420597) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 221576 + ... + 221613.

It is an arithmetic number, because the mean of its divisors is an integer number (2215950).

Almost surely, 2^8420591 is an apocalyptic number.

8420591 is a deficient number, since it is larger than the sum of its proper divisors (443209).

8420591 is a wasteful number, since it uses less digits than its factorization.

8420591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 443208.

The product of its (nonzero) digits is 2880, while the sum is 29.

The square root of 8420591 is about 2901.8254599476. The cubic root of 8420591 is about 203.4452359645.

The spelling of 8420591 in words is "eight million, four hundred twenty thousand, five hundred ninety-one".