1591328139 has 4 divisors (see below), whose sum is σ = 2121770856. Its totient is φ = 1060885424.

The previous prime is 1591328131. The next prime is 1591328143. The reversal of 1591328139 is 9318231951.

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 1591328139 - 2³ = 1591328131 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1591328139.

It is not an unprimeable number, because it can be changed into a prime (1591328131) 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, 265221354 + ... + 265221359.

It is an arithmetic number, because the mean of its divisors is an integer number (530442714).

Almost surely, 2^1591328139 is an apocalyptic number.

1591328139 is a deficient number, since it is larger than the sum of its proper divisors (530442717).

1591328139 is an equidigital number, since it uses as much as digits as its factorization.

1591328139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 530442716.

The product of its digits is 58320, while the sum is 42.

The square root of 1591328139 is about 39891.4544608241. The cubic root of 1591328139 is about 1167.4902099392.

The spelling of 1591328139 in words is "one billion, five hundred ninety-one million, three hundred twenty-eight thousand, one hundred thirty-nine".