1591591 has 8 divisors (see below), whose sum is σ = 1696464. Its totient is φ = 1488000.

The previous prime is 1591589. The next prime is 1591621. The reversal of 1591591 is 1951951.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1591591 - 2¹ = 1591589 is a prime.

It is a super-2 number, since 2×1591591² = 5066323822562, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1591511) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4081 + ... + 4453.

It is an arithmetic number, because the mean of its divisors is an integer number (212058).

2^1591591 is an apocalyptic number.

1591591 is a deficient number, since it is larger than the sum of its proper divisors (104873).

1591591 is a wasteful number, since it uses less digits than its factorization.

1591591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 641.

The product of its digits is 2025, while the sum is 31.

The square root of 1591591 is about 1261.5827360899. The cubic root of 1591591 is about 116.7554489736.

The spelling of 1591591 in words is "one million, five hundred ninety-one thousand, five hundred ninety-one".