1091559 has 16 divisors (see below), whose sum is σ = 1693440. Its totient is φ = 612480.

The previous prime is 1091551. The next prime is 1091561. The reversal of 1091559 is 9551901.

It is not a de Polignac number, because 1091559 - 2³ = 1091551 is a prime.

1091559 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1091551) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 799 + ... + 1679.

It is an arithmetic number, because the mean of its divisors is an integer number (105840).

2^1091559 is an apocalyptic number.

1091559 is a deficient number, since it is larger than the sum of its proper divisors (601881).

1091559 is an equidigital number, since it uses as much as digits as its factorization.

1091559 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 950.

The product of its (nonzero) digits is 2025, while the sum is 30.

The square root of 1091559 is about 1044.7770097011. Note that the first 3 decimals coincide. The cubic root of 1091559 is about 102.9632885160.

The spelling of 1091559 in words is "one million, ninety-one thousand, five hundred fifty-nine".