581391427 has 4 divisors (see below), whose sum is σ = 590922496. Its totient is φ = 571860360.

The previous prime is 581391409. The next prime is 581391467. The reversal of 581391427 is 724193185.

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

It is a de Polignac number, because none of the positive numbers 2^k-581391427 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 581391427.

It is not an unprimeable number, because it can be changed into a prime (581391467) 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, 4765443 + ... + 4765564.

It is an arithmetic number, because the mean of its divisors is an integer number (147730624).

Almost surely, 2^581391427 is an apocalyptic number.

581391427 is a deficient number, since it is larger than the sum of its proper divisors (9531069).

581391427 is an equidigital number, since it uses as much as digits as its factorization.

581391427 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9531068.

The product of its digits is 60480, while the sum is 40.

The square root of 581391427 is about 24112.0597834362. The cubic root of 581391427 is about 834.6214484011.

The spelling of 581391427 in words is "five hundred eighty-one million, three hundred ninety-one thousand, four hundred twenty-seven".