1591889 has 4 divisors (see below), whose sum is σ = 1714356. Its totient is φ = 1469424.

The previous prime is 1591883. The next prime is 1591901. The reversal of 1591889 is 9881951.

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

It can be written as a sum of positive squares in 2 ways, for example, as 478864 + 1113025 = 692^2 + 1055^2 .

It is a cyclic number.

It is not a de Polignac number, because 1591889 - 2⁴ = 1591873 is a prime.

It is a super-2 number, since 2×1591889² = 5068221176642, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1591883) 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, 61214 + ... + 61239.

It is an arithmetic number, because the mean of its divisors is an integer number (428589).

2^1591889 is an apocalyptic number.

It is an amenable number.

1591889 is a deficient number, since it is larger than the sum of its proper divisors (122467).

1591889 is a wasteful number, since it uses less digits than its factorization.

1591889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122466.

The product of its digits is 25920, while the sum is 41.

The square root of 1591889 is about 1261.7008361731. The cubic root of 1591889 is about 116.7627353833.

It can be divided in two parts, 159 and 1889, that added together give a 11-th power (2048 = 2¹¹).

The spelling of 1591889 in words is "one million, five hundred ninety-one thousand, eight hundred eighty-nine".